Best bus is one you actually have!
On a more serious note (B Flat?) while it's one thing to have some idea as to what you think you need, getting too hung up on details will result in you NEVER buying a bus. Deciding to have a longer bus over a shorty is one thing. Holding out for a manual tranny with over drive and rear engine with emergency door in the middle... exactly in the middle not slightly off and it can only be XX number of feet long because that is what your floor plans dictate, the ones you drew up two years before you ever looked at a bus.. etc.
Why can't you haul your motorcycle on a lift. I've seen many RVs with a motorcycle lift that also tow a car behind them. Or do what many in our current park (and previous parks) do... pull a little pickup truck and put the motorcycle in the truck bed.
As for not needing a "hookup" every night, we didn't need a hookup every night with the Class C... it had two 18 gallon waste tanks, an 18 gallon fresh tank, a crappy POS Onan generator, a SINGLE 12vDC deep cycle marine battery from Wal-mart. Longest trip we did in it was from NC to NM. It was 11 nights on the road we spent time in two campgrounds (2 nights in Benbrook COE and 1 night in Harry McAdams State/County park). All other nights we spent in parking lots. You don't need much to be able to park in a parking lot to sleep.
I would LOVE to have $10K to spend on the bus. It would be finished right now! And I'm sure I would not have spent as little as what we have spent (and will spend).
I suggest that you sit down with a couple pieces of paper. Answer some questions (just to get you started). Really put some thought into these questions. You need to think about now or near future as well as several years down the road which involves a great deal of What If's:
-- Will you be fulltiming, long timing or weekending. Fulltime is living 24/7/365, long timing is spending 2 to 6 months or longer stretches in the bus. Weekending is weekends or spending a week or so at a time.
-- You have a large furkid. So where will you sleep?

You need to take into account of the space your furkid will be occupying while you watch TV, cook, eat and sleep. Those pesky food bowls for the kiddies tend to be underfoot a lot, where will you put them? What about the furkid food? Where will you keep that.
-- Number of adults & kids to be living in the bus NORMALLY at the same time. Then you have the guest set up. We don't do "guests. When our kids came to visit, they stayed in a hotel. When just the one came to visit, she slept in the back of her Jeep.
-- Do you NEED a table to eat at? Really do you? We don't nor do many others. We tend to eat in front of the TV. Always have even when we had a dining room. We have a couple of small folding aluminum tables that we use as tables when we need to have a table. In nice weather, we tended to eat outside at the picnic table. We do need to pick up a folding table to use as a picnic table. Those picnic tables are looking rougher every year!
-- Where do you plan on normally staying (multiple answer question!!!) private/commercial campgrounds, public campgrounds (may have limited hookups and 30 amp max power), parking lots or boat ramps, boondocking, friends & family yards and driveways, your own lot? And HOW OFTEN!
-- Do you plan on cooking in or eating out at restaurants? Cooking in means you need to be able to store more food (fresh, frozen, canned). Also means you need serious cooking appliances as opposed to cooking appliances more suited to a couple weekends as year.
-- Do you plan on using laundromats, hand wash/tumble washers (requires a line to dry clothes on ... frowned on in commercial parks and some public parks) or have your own washer & dryer. This will influence the amount of clothing you carry.
-- Will you chase the sun or stay in one place for long periods of time? Where do you see yourself staying? We certainly did not expect to be staying, long term or short term, in a place where the temps get below freezing at night. Temps influence your winter proofing measurements. Temps influence your cooling measurements. No matter what... you can't have too much insulation and you need to have thermal breaks!!
-- How long do you want to go without hookups? Will you be frugal with water, etc?
-- What kind of fuel do you want to use as your main heat source. You will need heat even in a South FL winter. You will need a back up in case you are unable to use your primary source of heating fuel.
-- Stuff storage requirements. Your stuff will expand to fill all available space and then start to push you out. How will you thin down your stuff and can you use alternative stuff that takes up far less space (like paper books & mags vs electronic books and mags). What do you own that you do not want to give up? You don't have to give up everything. I kept several hings & incorporated them into the bus (king size 4 poster water bed now holds a standard full mattress, cedar barrel top chest David made me for my wedding present sits at the foot of the bed, 30" LP range that we bought not long before we decided to fulltime in the Class C, 1800's claw foot rocking chair, 1926 Craftsman oak fireplace mantle, old rock maple trestle style end table, Aladdin kerosine lamp, 1954 German key wound anniversary clock my Dad gave me, an oil painting I like and a signed/numbered lithograph of a gristmill outside of Greenville GA plus a few leather bound books that I prefer to hang on to). Decide what you don't want to live without, the things that make it "home" and then figure out how to build them into the bus design.
--Energy. Will you need to put a generator under the bus? Will you have PV panels? What size battery bank will you need for the "house"? What type of battery will you use (and will it fit in the battery compartment)?
-- Transportation. Other than the bus. How will you get around once you pull into a site? What is involved in taking your transportation with you?
Once you get those question answered (plus what ever notes you come up with) you need to have two sheets of paper. One sheet is your must haves. This will include the minimum you will need. The other paper will be your "wish" list. Next you will start price shopping. You want NEW prices. I don't care that Bubba-who-lives-down-the-road said he would sell you the old RV that hasn't been used in decades parked in his back yard real cheap. Look on the internet and get new prices. Use Camping World full price. Don't use any discounted prices. Get prices for your bare minimums and your dream list. Get as many prices as you can. Add up each sheet. This will give you a vague idea of the range your conversion will cost you. Low end and high end. And this does not take into account your bus shell.
Next take a sheet of paper and do a general layout to determine how much space your bed will eat up (our island bed takes up the full 10 ft behind the rear wheel wells including walk space), how much space your bathroom are will eat up (go into your house bathroom, flip the toilet lid down and sit... how much room do your feet take up in front of the toilet seat? Stand up, how much space did you use to stand up?) Go to someplace like Lowes or Home Depot. Try to stand in the smallest shower stall they display and "wash" your hair and feet. Don't forget to drop the "soap".
Next is your field trip. Do you have a digital camera or one on your cellphone. You also need a small note pad, a tape measure and the camera. Now go to your nearest RV dealership. Take your time, you are not really there to look at RVs. You are there to look at SPACE. Look at the walkways. How small can you comfortably go. note down the smallest walkway you can walk down normally (not sideways) note that measurement down as your minimum. Find one that is "comfortably wide" and note that one down as the widest. Check out the bathrooms, take pics in addition to measurements. Pretend to use the facilities. Step into the shower and wash your hair, drop the soap. Flip the toilet lid down and sit on the toilet. Do you have enough room to wipe? Stand up and pretend to pull your shorts up, Do you have enough room? Take measurements. Collect literature with floor plans (write notes on them) Warning! an "all-in-one" bathroom where the toilet, shower and sink are all in the same shower stall is not as neat as it seems. Use one only as a last resort. The floors are always wet and/or muddy. They might be okay for a weekend but for fulltiming, they suck. Check out the bedroom. That narrow aisle around the bed... can you walk in it without falling over? How about the clothes closets. At minimum a single person with 8 days of clothing needs 18". 24" is fairly spacious. Check out the galley (kitchen). Okay, I hate what RV designers do to galley kitchens. Galley (single wall or double wall straight runs) are the most efficient kitchen layout. They are the worst kitchen designers. They waste far too much space. I used to be a Kitchen & bath designer. I specialized in small kitchens. A small kitchen is much harder to design well than a large kitchen. You want to look at counter top spaces. If you have no dishwasher, you need enough counter space next to the sink on at least one side to put a dish drainer. I don't care if you think you will stack your dishes in the drain rack in the "rinse" bowl of the sink. You need space next to the sink. You need a double bowl sink. You need enough space next to the range to set a plate or cookie sheet on the counter. You need at least 6" between the edge of a burner and the closest wall. Pretend you are cooking in the kitchen. Take lots of pictures.
One last tip (finally! bet you thought I would go on forever)... You need to be able to pick up and leave fast. While a skoolie is much better built than an RV, you still will need to leave places due to storms, floods, fires, etc. The faster you can pack up, the faster you can leave, the less chance you have of being caught in the path of destruction. To me, best scenario, would be crank up the bus, let the air build up, while that is happening, go outside: dump the waste tanks, close the valves and stow the sewer hose, stow the fresh water hose, unplug from shore power. Inside: secure the refrigerator door, secure the cabinet doors. Secure anything loose. Take the dog out to go (which it won't), dump the pet water, secure the dog (mine always just climbed in the bed and slept), check the lights on your walk around to make sure everything is ready to go and you haven't left anything. GO!
A place for everything and everything in it's place. Means less clutter, less chance of stuff taking over and less chance you get caught in a bad situation that you could have avoided if it didn't take you two days to get ready to go.