looks like a pretty good bargain you got there
seat wise, rs4s's never came with electric leather seats, but i'm pretty sure they only need a 12v power supply to move
they might also be heated, which would need some switches and wiring
thats also the stock bodykit
I'd check that the timing belt was changed at 100,000 kms and do all the fluids (gearbox and diffs) just to be safe