You have to factor in the cost of not staying in B&Bs. I always used to kip in my lazer tent but it gets a bit tiresome when its raining all the time.
Kitted out campervans are ridiculous but then again you may get 20yrs use out of one.
I have probably slept in my van nearly ten times this year and I cant fault it. Having the high roof is def the way to go. You can stand up and get dressed.
Also the option of starting the engine and getting warmed up. Brilliant for BG support.
After a race I put the table up and sit in the chair with a bit of comfort.