I have wondered about this, given the level of stress in my current job! Do you reckon there's much of a market for this sort of 'self-built' conversion? Don't most people want something that looks all factory built and crisp and clinical?
Also, I'm not sure the finish I'm getting is really good enough to sell!
There is always a market just depends: who, what and how much, also how you can reach that market. I can only suggest you maybe have to offer various Products - That could be say a van just lined and insulated - buyer fits out the rest and all the ways up to a fully fitted van. If the buyer was well flush could you do a custom fit?
Even doing the leg work for parts and accessories is worth it to the cash rich and time poor.
I would not know where to start with the legals but a hire service ?
Time wise - would the time you take not decrease as you did more and gain experience.
And for sure you got up and got on with it - when many just sit and dream - Well done.
( I'm just sitting about drawing and cutting cereal boxes to plan my eco cabin = dreaming)