If a Rickenbacker 4003S has a small chip in the finish, how much approximately does that affect the value?
Also, what about the age/year? A 2019 versus a 2015, for example?
So, a 2019 in "like new" condition, versus a 2015 with a chip in the paint.
2019 vs 2015 makes little difference, all else equal. It changes when you get into different eras where production changed. One of the biggest recent examples would be RIC making the bass and 620 cresting wave horn smaller. Some weirdos like me still prefer the older larger horn, so I would value a 1988 4003S in very good condition more than a 2015 4003S in near mint condition. Not necessarily more money, but I'd just rather have it, and demand is half of the supply/demand equation in economics! And it depends on the buyer too... are they going to rock out with it on gigs, or baby it/hang it on the wall/play it at church occasionally? I am in the former group for sure, so I like "used but not abused."