Yes, the bird crap is the biggest culprit!
Your area may have places that rent out paint booths. We have a few around here, but as I mentioned, I decided to go with someone to do it after I weighed out the costs of me doing it and having someone else do it. If I used my garage, I would have to spend a lot of time in the prep. I would need to set it up my garage like a paint booth; line the walls with clear plastic so the paint does not get on everything I have in the garage. I would also need to make some sort of exhaust vent either under the garage door or in the window with a strong fan. That also requires you have a return vent with a filter setup. I also was not real confident in the mixing of the paint part of the shooting and the gun I have is not really the best for doing a car. I guess a Wagner spray gun would not work... (just kidding). The cost of a new gun, paint supplies, plastic and all the time to sand and prep the body with Bondo, etc. It is a lot of work. As i mentioned, I did as much as humanly possible to prep the car for the paint shop. I even went to the junk yard and got another hood off a 94 for them to use. My hood had a dent in the very front that would have taken more time to prep than just replacing the hood.
The sunny pics are after I drove the car home. The tail lights are in only for driving purposes and had one bolt holding them in. Same with the mirrors, one bolt holding them in. I pulled the inside door panels out so they could easily remove the mirrors. You can see the replaced hood before painting. It was a turquoise blue and then the after spray is the sunny pic is where the the hood is gold. The first pic is the car before I pulled the rear side quarter windows out. I stopped by one day to see how they were doing and it was in the back prep area. The windows where covered and it was being prep'd for paint after all the sanding and body filling of the dents. When I first went over to get a quote, they went over all the dents and dings that needed to addressed and mentioned the work it would take to straighten the hood, do the pin stripping, etc. That is when I started getting the idea I would strip down everything for them to keep the costs down.
Go get a few quotes and see what it costs now. Ask how much to just drop it off and they pull everything as apposed to you bringing it in stripped and see if there is a big diff. You might be surprised. After the paint job, I did my own pin stripping, which turned out better than when a dealership did my Town Car after an accident. I read several articles about doing the pin stripping to get an idea of the little things, like how to place the stripping at the door / body junction and what to do with double pin stripping, etc. The paint job was done some 8 years ago and still looks great. I went around the corners of the car yesterday buffing out the paint marks from A-holes that can't pull out of a parking space without nailing the corner of your bumper... WTF I ask you?!
Good luck!
PS: The pic of the replaced hood before painting, the driver corner of the bumper is where someone was backing out of a parking space and nailed my car. They just drove off, but a witness was kind enough to leave their phone number with a note that they saw the whole thing happen. I tracked the culprit down, found out they were not well off and my wife said "let it go, looks like they could not afford insurance, let alone to pay you for the damage". I lived with that for 10 years?! Waiting to get a paint job can be debilitating with crap like that on your car. But the key to spending the money to get your car painted is "are you going to keep the car for another 10 years?". That is what can be the deal breaker. I spent a lot of time over those years looking at other Cougars like mine, in much better shape and wondered if it would be cheaper to just replace the car for the price to get a paint job.