Some of the reasons I no longer deal in coins:
1) The lady that says she has "gold coins" to sell and is flies off her rocker when I inform her that the Sacagawea dollars the mint advertised on TV as the "golden dollars" contains no gold and are worth but a dollar. I drove 15 miles for this.
2) The guy that says he has some silver coins he wants me to look at. When I get there he rolls out one of them glass water cooler bottles (the huge ones). The bottle breaks when we try to lift it requiring a shovel to scoop everything up. I finally get it home and after hours of sorting there is $25.75 face value of silver dimes. I told him to do himself a favor and dump the rest in a Coinstar machine. He replied he wanted me to sort out the wheat cents. By then, I didn't care if there was a 1909S VDB in there. I printed out a list of the few valuable wheat cents and gave it to him.
3) The lady with the fake US Trade dollar that I would not sell on consignment. She accused me of trying to rip her off. Why would I tell her something is a fake and not offer her anything for it? She phoned me to tell me she was sorry after getting caught trying to sell it on Ebay as genuine.
4) The guy with a decent collection of Peace and Morgan dollars he inherited. Even a couple Seated dollars. He had scrubbed them with silver polish and ruined them. He had given his kid some and one was a nice 1889CC which I had certified and sold for him. He netted $675 for the one coin. I wound up buying the ruined coins because he found out my offer was a lot more than the local coin shop. Had a heck of a time unloading them for a meager profit.
5) The people who want you to pay high retail for a piece. Never mind that I have to drive out there and back, pay for certification from PCGS or NGC, pay Ebay and Paypal fees, drive to the refiner, pay a coin shop a percentage for consignment, or handle the sale to another collector. I should do all that for free. They really torqued me. After they find out I was honest and was offering the lowest fee to handle the piece and doing everything I could to get them the highest price for their holdings, they would call me to come back. I told them that I do not need the aggravation of dealing with them and to sell it themselves. One guy called me 5 times and begged me. No way!
6) Coins that people think are worth more because their "Granddad loved them". Yeah, thats why he dumped them in a coffee can and drilled a hole in some of them. One time I saw some really nice and rarer date Barber halfs that someone had drilled out to use as washers. Of course, the owners think that they are still valuable. Why did people call me if they are such experts on the worth of a piece? They nearly always refused to believe that something had little value.
7) I would always require a family member be present when dealing with an elderly seller. It ws amazing how many neglected senior citizens there are and have no one to watch over them. If the elderly person seemed broke, I would often take it as a loss and handle it for little to no profit. They often had the most desirable pieces. In cases where they would show me what other offers were made, it made me sick to see what the coin shops had offered them. Pennies on the dollar value. The rip off factor is high and I no longer wished to be associated with it.