As said, new cars can be sh*te or good.. depends... normally if it's a brand new car we would either get the car delivered straight from the dealer to us or get it brought in as soon as otherwise possible. It's best to stress on the dealer that you DO NOT WANT THEM TO WASH, POLISH, OR PREPARE THE CAR for you.
Many will often try to be like "oh we can't deliver a dirty new car to you" - but you need to enforce upon them that you do not want it washed or polished..
We managed to do a brand new F30 335 xdrive in one late afternoon..arrived at something like 3pm and he drove it away at 10) -
that was driven from the dealer to the unit and we even managed to cquartz it ... only a few sections on a few panels needed any sort of polishing work and fortunately they were fairly light so came out in one or two passes with a fine abraisive so no need for refinement.
Usual is 2 or 3 days (but this depends) and usually around the £200-300 Mark...the last new car detail we did was a Fiesta from my memory which came in at £220 or there abouts with a decent wax... Cquartz Ceramic coating would add another £150 or so to the price as we need the car for longer really to let the coating properly cure and the extra time of application. this is what i had on my GTI and it was still beading away after 6 months without any top up products applied.
at end of the day we generally give a fixed price and sometimes you get less work than anticipated and sometimes (nearly always) you get more but that's the way it goes.
The normal cost for an enhancement is around the £350 on a Golf Mk5 sized car (most of our work is enhancements which gives you the kind of difference you get is as below) ..
We are based in Newbury but a bit far away from you- Although I have a few write ups in the detailers section if you were so interested and there's always the train home
