I recently took my Mk3 3 for a price to repair the front footwells, bulkhead and a small repair in the boot. Wanted £500 for it so I did it all myself.

Guessing, they'd probably want about 3 days, so that's 24 hours at say £30 per hour plus parts/paint so I guess you'd be looking at £900 or so providing they find good stuff to weld to.

It took me about a day to do a wing, taking it steady.

hope that helps
Ant