You might be overlooking the VAM-factor too. For example, a common 1880-P in AU would sell for $30-$50 typically. Put a set of "ears" on the second '8' and you have a $4K coin (
VAM 8 ears). It's an overdate variety where the top of the '7' from 1879 barely shows on the top of the '8'. It's very hard to see and extremely rare and desirable.
This is just an example. There are other factors besides date, mintmark, and technical grade that will influence the final price. Eye appeal is important to consider, too.
If you're new to this it can be overwhelming and you have to rely on the experience of others to get a fair price. Who do you trust? You have a couple of choices here ... take them to a local expert for their opinion. If they are interested in purchasing them, I would get a second opinion on their appraisal. Post them here and we'll offer our opinion without charge or expectation of purchase. Lastly, you can delay your sale and learn to be self-sufficient in grading, variety attribution, and appraisal. The last option usually creates the best return on investment.
