savings in customizing a Ram ProMaster vs buying a Travato

It will cost nowhere near $20,000 to build a very nice camper van with nice bed , portapotti , kitchen using my(stolen idea) sink method , portable stove,battery bank, compressor fridge , ceiling vent fan(s) . Gary at the Promaster forum(I posted link earlier. Page 8 has pics) built his for $3000. I would hire a carpenter to do mine because my wood skills are nil. That would be biggest cost.