Case in point I will show how I came to make my most recent purchase. The coin is an 1842 Seated Quarter in VF-25. If you check Heritage you will find they had not offered a single example in this grade in the last 11 years. If you checked Great Collections you would find they have sold 7 coins since they opened and none in this grade. You will find the entire NGC/PCGS combined population is 153 coins, with only 15 in grades 20 or 25. The CDN will tell you their is a price jump of more than 150 dollars at the next grade. The coin shows up in higher grades(more slabbed because worth more), but I have my budget so. There you go. James
For proper retail pricing analysis I refer to CDN CPG or PCGS Coin Facts, NGC Value, otherwise just do cost plus. Beyond that negotiable and confidential with buyer. My bid / offer a pct of what feel can sell for. I may look at auc data off CF or CPG. Purchased items then marked up per business goals, current Mkt conditions.
Doing your research may be a good idea if you buy common gold or try to make good deals to resell. It’s almost pointless though if you build a type set or collect mostly toned coins where prices can go through the roof. Same is true for varieties such as R5 (or even scarcer) Bust halves.
To each there own. My Oma used to say "there are two ways to get an education, but one way is much harder than the other". James
I'm going to quote myself here and post an interesting update straight from the NGC boards from NGC support. Found it to be interesting. "Hello @Vess1, thank you for contacting us. The NGC US Coin Price Guide shows average dealer retail prices based on actual, documented transactions and other information reported by collectors, dealers and auction houses for NGC-certified coins. Unfortunately, if there isn't any report sales of a particular coin in recent times, then only the previous history data will be shown. Kindly keep in mind that NGC does not assign values on coins or collectibles. Please let us know if you have any additional questions. Thank you!" IMO it should be a good source then, except that sometimes sales aren't reported. This begs the question, who can report a sale?