even though geofkaye could be called my mentor, and his advice is probably more valuable than mine, I will put in my 2 cents.
I bought a MDT 24' straight truck for $9000 and have spent (to date)about $5000 and six months of hard labor on conversion. I plan to be using it in about 2 weeks. I owe it to:
1) research and asking geofkaye
2) internet buying (like craigs list)
3) a good set of tools
4) hillbilly ingenuity
Doc Weaver