Before you guy cut huge holes in the sides of your buses you need to do two things.
#1. Go over to
Ian's forum and do searches on both the current forum & in the archives to read up on the folks who added slides to their buses. They will have links to all kinds of info.
#2. Go to two or three RV forums and read up on the problems folks have with slide outs.
HWH sells mechanisms to private converters. They used to have PDFs online but I don't know if they still do. Their PDFs were so informative that David worked out how to build a low priced system for the Eagle. We later dumped the idea because the cost per square foot was far too high. After much reading about the pro's/con's of slide outs we decided against it. Since we were planning a fulltime coach, we knew that the cold weather would cause us problems with a slide out. So many problems. Most folks that are pro-slide outs fall into a few categories: never had them (like the idea of gaining an 18" deep x 10ft wide strip of extra space), haven't had the slide outs very long or use the RV only for week end trips in mild weather, want to keep the "resale" value up on their RV (these folks also don't use the bathroom in their RV because they want to keep the black tank "pristine" for resale value). Downsides to slide outs is they leak water, drafty, mechanism breaks/jams up often. They creep out driving down the road. When the thing breaks down it's generally in the "out" position which means you aren't going anywhere until you get the thing shut down. The RV may suffer from "weak" areas from the installation of the slide outs. For us, it just wasn't worth it. Some RV sites will not let you open up the slide out without hitting a tree (that was from personal observations while living in public parks). I also object to being in a campsite that I am paying for only to have some moron pull in next to us, plant their RV right along the edge of the site then open their damned slide outs into OUR space. And yes, we have had that happen (one missed hitting our food cart by 4"). I bitched, demanded a severe reduction in site rental (didn't get it) and the other RV had to reposition their RV... and NOT open their awning on the other side (no room). Older RV parks are not always wide enough to allow an awning to be deployed on one side of the RV and slide outs deployed on the other. With slide outs, you may need to be looking for "Big Rig" sites that are longer & WIDER. They also tend to only 50 amp power and costs much more. You need to think about how you will use your bus before you stick a slide out in it.
If you go to
Forest Camping which is a National Forest Campground Directory, you will find lists of campgrounds. In the descriptions is a section that says what the size of the "parking apron" is. The parking apron is the space where you park your bus/RV AND your vehicles that you drag along. Note the WIDTH and bear in mind it does not take in to account those pesky trees!...
(example from one campground in Lincoln NF in NM)
RV INFORMATION
Hookups: None
Group RV Sites: No
No. RV Pull Throughs: 3
Waste Station: Yes
Potable Water at Waste Station: Yes
Average Parking Apron Size: 12' X 43'
Our Fav campground near Clayton GA
RV INFORMATION
No. Full Hookups (includes waste): 0
No. Water and Electric Only: 26
No. Water Only: 0
No. Electric Only: 0
No. RV Pull Throughs: 3
Waste Station: Yes
Potable Water at Waste Station: Yes
Largest Parking Apron Size: 12' X 70'
Indian Boundary... popular campground off the Cherohalla Parkway in TN
RV INFORMATION
No. Full Hookups (includes waste): 0
No. Water and Electric Only: 0
No. Water Only: 0
No. Electric Only: 88
No. RV Pull Throughs: 1
Waste Station: Yes
Potable Water at Waste Station: Yes
Largest Parking Apron Size: 10' X 40'
Cable Cove near Fontanna Village NC (there's only two of these wide ones)
RV INFORMATION
Hookups: None
No. RV Pull Throughs: 0
Waste Station: No
Largest Parking Apron Size: 16' X 74'
Standing Indian near Franklin NC
RV INFORMATION
Hookups: None
No. RV Pull Throughs: 4
Waste Station: Yes
Potable Water at Waste Station: Yes
Average Parking Apron Size: 10.5' X 52'
Van Hook Glade between Franklin & Highlands NC
RV INFORMATION
Hookups: None
No. RV Pull Throughs: 1
Waste Station: No
Largest Parking Apron Size: 10.5' X 57'