I had to repaint my front bumper. The cost to take to the shop and have it done correctly was $300. Be certain they get the corners the correct colors on those C4s.
The clear has to be removed and resprayed. You can get away with just using clear coat as long as none of the paint color has flaked off. A friend of mine just did his 87 this way. The clear was peeling off. The clear was stripped and re-sprayed. It looks new.
As said above. Also if there is no other damage then hitting it with 3M britepads and prep for clear application would be all that's needed. The nose is easily isolated either by taping off and bagging the rest of the vehicle or removing the nose. I'd do a normal first coat with base flash time then follow with a second wet-on-wet coat. Wouldn't hurt to have flex added to the urethane clear.
The shop I used removed the whole front bumper, which worked out very well for me. They were able to get it back on perfectly. The damage was fairly minor; I had barly bumped into a trailer drop hitch and there was no structural damage at all to be repaired. I was just much more comfortable having the whole bumper pulled and repainted.