All I can suggest is use the forum, and other sites to appeal to buyers. Like I said, my car wasn't for sale, BUT it is extremely important to know your car forward and back, and keep it clean. I'm not talking vacuumed, I mean you could eat off of any part of the frame. That separates you right out of the gate from 90% of the other owners, and makes a rare car more valuable. Also if you insist on putting in an aftermarket radio, or other mods, make sure to keep original parts, and not cut stuff up, so it can all be undone. Of course in some cases this type of ownership isn't practical and if not, that's ok, but keep it clean....maintained and try your best to know all its quirks and how to fix them. Take really good and detailed photos, and be honest about your car. All of it. Dont hide the defects. It's not fair to you, or the future owner. If they don't want it, no biggie, someone else will....
In my quest for another type of car, I have already passed on multiple cars due to hack job aftermarket stereos, or incorrectly installed (non tuned) procharger systems etc. You get the idea....