One thing for sure, after a trip like that, you will definitely be an experienced bus driver!
The amount of stuff you can carry is determined by the gross vehicle weight rating (GVRW) It may be as high as 36,000 lbs depending on the bus you buy. Find a scale and get the empty weight and compare to the GVRW and you will know how much stuff you can load.
For driving experience, best case would be to find an experienced truck driver and have them go for a ride up and down a big mountain pass in the bus you buy to give you advice on how to handle your vehicle. Going up, it's important to know how to NOT overheat things and cause catastrophic failure of multiple components. Coming down, it's important to know how to properly slow the vehicle so you don't overheat the brake system and cause fatal failure with a runaway 36,000 lb missile!
Read this thread. It's all about a guy who recently used his bus to move from Ak to Ga. Tons of helpful info in there.