I presented the car at IVA myself, this was on the basis that I had built it myself and wanted to see the whole process through. I did have a PBC done first for peace of mind and so that the dealer could fit an IVA compliant steering wheel they lent me. They didn't find anything materially wrong with the car but had clearly 'adjusted' a few thing for me - better fixed the tyre goo in the boot, added a lock nut to the steering column grub screw and re-bled the brakes for me. They also did a 10 mile test drive to bed the brakes in - I presume they did this on trade plates. So, in my case it was definitely a good idea to have the PBC done in advance. I trailered the car to the IVA, as my insurance company was a bit vague on the cover if I drove it myself. I actually enjoyed the IVA, I was asked to help with the process and they took the time to explain what they were doing all the way through. We chatted about how I had approached the build and laughed at some of the Caterham 'idiosyncrasies'. They were very professional but equally quite keen to pass the car if they could. I had one issue with the steering not self centreing as it should, I was invited to correct it while they had a cup of tea, which I did with a bit of toe out. Obviously I don't know how it would have done if the dealer had presented it, I suspect it would have passed too. But I figured I would be paying someone to do what I could do for myself plus their charges fro transporting the car there and back.