Greetings & Welcome!
I would strongly suggest a cheap older class B camper van for you. It will save you money up front, retain a higher resale value, will be better quality than 99.9% of any of the DIY builds, and be move in ready.
The promoters who suggest cargo vans and DIY are doing it for their own benefit, not yours. They don’t care about your comfort or convenience, they make their money by conning people into making poor choices and expensive purchases.
Living in a box without windows is pure torture for most people, regardless of how nice their interior is. I got conned into trying it, and it was the most miserable year of my life, and I lost over $30k in the process. Other than that expensive nightmare, I have never paid more than $2500 for a camper van or motorhome, and all of them were 10,000% better than that cargo van, even though it’s interior was far superior than most factory built ones. The problem was it was dark, cramped, claustrophobic, depressing, and inconvenient. It was also a money pit, and the promoter’s solutions were to continually throw more money at it.
Don’t believe the BS that cargo vans are stealthy either, they are the exact opposite. The public considers unmarked cargo vans to be creepy, and they are huge targets for thieves hoping there are expensive tools inside.
20-21 foot small motorhomes can still be parked in normal parking spaces too. I had a very nice 18 footer at one point in time, and it was actually much easier to drive than the cargo van was, and much more comfortable too.
Height can be a very important factor for many people too. If it’s tall enough to stand up inside, it’s too tall for most parking garages and drive-thru’s. I had a number of low top camper vans, and I really miss the ability to utilize parking garages and drive-thru’s. Strangely enough, I never missed the ability to stand up inside. The only compromise was showering while seated, and now, even though I have a high top, I still prefer showering while seated.
Good luck & keep us posted, we’re here to answer any questions too!
"Opportunities are everywhere, but only action makes it happen." ~ Van_Dweller