Often there are parts for sale. Some are original used, or NOS - some still in the original boxes. And of course reproductions.
If you have a stock pile of parts what will bring the high money? The mechanical engine drive train parts? Or the sheet metal body parts?
And of course the miscellaneous stuff - electrics, glass, and the infamous water pump?
Apparently, Arkasas dealer tags are the current hot item!
But really, as Kim says, the early stuff, aftermarket "Go-job" speed goodies or anything that isnt being reproduced, and is in good ( original, usable or restorable) shape.
I've seen a lot of non-"T" trim pieces ( stainless or chrome body mouldings, tailights and emblems) go for serious/stupid $$ just because they are not being reproduced by anyone and they tend to be the parts that catch the eye initially and "finish" a restoration
Swivel gear for speedometer. Aftermarket high compression or over head valve heads. OF Stromberg carbs. Any block, rear end or pan before 1916.
Anytime I try to buy something I'm told how rare and valuable the part is but anytime I try to sell something I'm told there were millions of them made and it has no value.
LOL Denny, ain't it the truth!
The price is whatever you are willing to pay! If the part is needed to make your car run, you will probably pay a lot for it, however, if it is just a spare or a part for another car, not so high. A good rule for NOS parts is the price of a reproduction part listed in the catalogs + more if the part is still unused and NOS. Old worn, bent, or rusty parts would not be worth much unless a body part not currently being reproduced. What I have found is that I look for some part I need and finally find one which is not in very good condition, but I need it. So after I buy it, I find a better one at every swap meet for less.
Most valuable part is a loved one in the passenger seat.