I bought a 15 plate panel van VW T5 a while back, November 2015 IIRC, with the sole intention of converting. If you want to carry more than 2 bikes and not use a towbar mount, you need a tailgate. SWB is fine for me, SWMBO, 2 kids and 2 dogs plus the 4 bikes on the back.
I had Uberbus fit the windows and an SCA 194 pop top (which is wonderful) along with a RIB seat on full length sliders (they call it FLUX). A very practical arrangement.
All carpet lining, electrics etc I did myself, and I fitted Evomotion Design furniture which is good quality and easy to build. Add a fridge and we're in business.
I hate to think what it cost, but after a life changing 2 years leading up to it, it was something I wanted to do so bit the bullet.