Patch it up how??
if you don't have experience in fiberglass then just take it to whoever painted your bumpers and ask them to do it. they should be able to with no problem and paint that spot at the same time. shouldn't be too much with an experienced person. i would say like $75-$100 would be a decent price but it also depends on how the person decides to fiberglass it. if you want smooth across the bumper like an opening was never there it'll be more since more work is needing to be done. if you just wanna literally plug it then a lot cheaper.
nick
