There is no doubt project cars can be a drain on your funds. We can try to buy the parts used, or find deals, but it still adds up. One way to help supplement these funds is to sell the old parts off your car. Believe it or not, some people seek original parts, and some just need parts to get their own projects rolling.
When I first started working on my '68 Camaro back in 2001, I didn't know what parts were valuable, and what was garbage, so I kept everything. I piled parts in boxes and labeled them for storage. Years later, I revisited these boxes while cleaning out my mom's garage. Some of the stuff went straight to the trash pile, like the 25-year-old iron water pump that was leaking from its seep hole when I replaced it. Other parts, like the original fuel level gauge, which I replaced with the tic-toc tach, were definitely worth keeping. The Mustang project is churning out dozens of used parts a month, so there is a lot to sort out. Unless the part is broken beyond repair, it's worth something to someone; it's just a matter of preparation and communication.
The preparation part is really important, and having a nice photo of the part is crucial. To get the best photo, I start by cleaning the part. I keep at least one gallon of Simple Green in my garage because it's a versatile cleaner that is paint-friendly, but can still loosen up some grime. Having the part clean is really helpful when selling it. No one wants to pick it up to look closer and get grease and grime all over their hands. Cleaning the part well also gives the illusion you took good care of the part while it was in use. (Ha!) After all of the road goo and dirt have been successfully removed, a quick coat of spray paint can make it look brand new. I was cleaning up a set of cast aluminum brackets that had started to show some corrosion, and wouldn't come back to their original luster with cleaning alone. I used Dupli-Color's aluminum engine enamel on these parts and they looked as good as new. Sometimes even replacing parts, like ball joints or bushings in control arms, and selling them as reconditioned can help you get more out of the sale.
The next part is the communication. Letting the right people know you've got the part they need is the goal. The Internet is a great venue to find these people, because more than likely, they're on there looking for you too. Forums specific to the type or car you're selling parts from is a good place to start. A little research can go a long way. If the part you're selling can fit many different cars, it's helpful to make a list of what it fits. For example, many parts on Camaros fit Firebirds and Novas, so listing what years of each model it fits will expose you to many more buyers. To get the most for your old parts, it's hard to beat eBay. It's also a great place to source a price for your used parts if you're going to go the local-sale route.
You might be surprised how much these parts can go for. The original steering wheel from the Mustang sold for more than the Grant steering wheel I replaced it with. So dig up those boxes of old parts and get cleaning!