First suggestion is pick someone local and figure out your build changes in as much detail as possible, including parts. I have spoken with Jeff at RVI and really like him and his work. However, when the time came to fix a lot of issues on my original build from CCV Chris from UJOINT recommened a Mike at Wicked Fabrication here in So Cal, local to me. He is getting more into the van world and has a pretty impressive van himself.
After seeing his work ethic and his work on the fixes we had planned for my van I had him redo a big portion of my interior and am very happy. It has held up very well so far. Mine isn't a normal build out because he had to work with and around the original build. I chose to stick with a futon mattress in back for sleeping comfort so it doesn't look as cool in the sofa position as SMB stuff but Mike can get custom work done also to look more offical. He also has the knack for sourcing quality parts without me having to monitor every single item as with some other folks.
If you want to see his work on my van you can skip the reading drama and just scroll to the photos:
Since the photos I had Mike do other work as well like make a custom removable swival captians chair base and mount for a captians chair behind the front seats. The chair swivels so I can chill and stare out the barn doors, it is great. I can pull the captains chair and put in the bench seat if needed still. He is a very skilled fabricator and if I had the cash would have him make a front bumper with winch.
Gooseberry had some running board type guards made for his van by Mike as well so you could contact him for reference also if interested.
I have also met Alan from SMB West a few times and he seems very customer orientated so if you have the cash and time that is always an option. I buy stuff from their site at times, actually reasonable prices and Alan always answers my questions. Just depends on what you are looking for.
Extreme Sport Vans/Wicked Fabrication
Phone : 818 535-5445