Finish on the spoiler of our 2004 HB was trashed due to sun exposure; clear coat was gone and the base was starting to give way to the primer or substrate. It was bad enough to be the first thing that caught your eye when looking at the car.
A discount body shop we've used with good results for bumper covers and other touch up paint work gave an unnegotiated price of $125 USD to repaint it, so imagine it could be done professionally for $100 to $130 in most places. However, I decided to go with a DIY bundle from Automotivetouchup.com. Their prep solvent, sandable primer, Aveo color base, gloss clear coat with sandpaper and spray handle ran about $58 delivered. The spray handle did not add much for this type of job, so would save the ~$4 if doing it again. They have a decent video tutorial on spoiler touch-up.
The results were actually pretty nice. Slightly darker than the original, but not really noticeable unless looking for it. The main question is how well their clear coat will hold up. I laid down 3 to 6 coats at each level, so there's a lot of material to burn through. Apologies for the poor quality on the before and after shots - "after" is the second one if there is any question: