Bus to Motorhome Conversion

Hey,
I have been looking at converting a State Transit Authority Bus into a Motorhome and i was wondering what bus would be the best to convert. There are a few things i want from the bus:
1. I am a pretty tall person around 6 '4 and i want to be able to stand up. I know this will probably involve the floor being lowered or ceiling raised. However i still want to have everything i need like a washing machine shower toilet, fresh water tanks aircon etc.
2. I want to be able to go pretty much anywhere
3. I have a maximum budget of of 25000
4. i Want the Bus to be pretty comfortable and roomy
Secondly
What would the Usable interior dimensions be
thanks
I have been looking at converting a State Transit Authority Bus into a Motorhome and i was wondering what bus would be the best to convert. There are a few things i want from the bus:
1. I am a pretty tall person around 6 '4 and i want to be able to stand up. I know this will probably involve the floor being lowered or ceiling raised. However i still want to have everything i need like a washing machine shower toilet, fresh water tanks aircon etc.
2. I want to be able to go pretty much anywhere
3. I have a maximum budget of of 25000
4. i Want the Bus to be pretty comfortable and roomy
Secondly
What would the Usable interior dimensions be
thanks