The Youtube route of viewing vans and getting ideas for build and products, using them as a bit of a pick & mix for your own is handy.
If you haven't looked at them already, some of the ones I think are good are:
Humble Road - US channel. That is a conversion of a Sprinter and I would say is a "no costs spared" approach. This build is also unusual compared to most as he uses "80:20" aluminium to frame everything out. Excellent product, but pricey (it is available in the UK under a different name)
Ourkaravan - US Channel. Another Sprinter, using 80:20 again but not such a dedicated Motorhome. Well worth a view
The Restoration Couple - UK Channel. Sevel Van (probably a Ducato) and a fairly standard British style conversion but very well documented and I think the chap does a cost breakdown at the end of the series.
Rickvanman - UK Channel. Enjoyable series of videos with a conversion on a limited budget. He has over the years done 3 different vans so you can see 3 different approaches and builds.
Van Tourist - Russian Channel. Another Sprinter again, but a nice build. I like his build as he has happened to take a very similar approach and use the same product types as I have as it happens. He has a costing at the end as well I think and that is still relevent as the products he has used are available in the UK and in fact many of them he actually sourced from the UK (the UK has the biggest self-conversion market probably in the world - I bet even bigger than the US as most US self-conversions appear to be very limited and basic).
Lots of others of course out there - Greg Virgoe is one that is widely quoted as a good one to look at and I have met a couple of people who based a lot of their build on Gregs work.
One thing to watch out for on all these youtube builds .... there are usually a real-time progression and what is done in one episode may well be redone differently later on, either because the builder found a better way, or maybe because what was done just didn't work! (There are some key examples of that on most (all?) of the channels listed above!). So watch until conclusion before emulating
. Ivan's Build (Van Tourist) is good as once he finished his, he has another series of videos of him actually using his van on a big trip around Scandinavia so you get to see what worked and what didn't so much. Rickvanman's channel is similar (except more like trips around the Coltswolds rather than the Arctic Circle)
If you goto the VW T4/T5 forum (
www.vwt4t5forum.co.uk), there are hundreds of build threads with all kind of different approachs. Many are very similar of course, but there are some real odd ones out there, and good if you are converting a smaller van.
Also visit the Quirkycampers website. This is a collection of self-build campers that are available for hire through quirky campers and you can see a lot of interiors there and get some ideas maybe - especially if you are a bong-inhaling hippy