Well for a start,, if that antique dealer has not actively kept up with trends and prices as well as what is actually selling,, he/she may be way off on the prices !! Without knowing what you are selling its hard to give a general value on anything !! Ceramics unless by known makers and marked as such generally do not sell well !!
I would certainly check with other places but you must understand that no matter what they say,, value is only as much as someone is willing to pay that night !! Tomorrow might be totally different !!
We look at prices and values sometimes daily here !! Why don`t you post a couple of pieces at a time here on the Q&A forum !! We would be happy to give our opinion on actual value !!
Provided the pieces you sell are not super large,,ebay might be the best bet !! I sell some glass ware with no problems by using heavy grade boxes from the dollar store that would be tossed or recycled and packing with the plastic grocery and dollar store bags !! Lets say I sold a vase,, I would use a box at least an inch or so larger all around than the vase,,plastic bags go in the bottom to fill that inch then the vase and pack tightly all around and inside the vase all the way to the top,,it must be snug in the box !! You can stuff bags inside other bags to make a pillow at top if needed,,close and tape !! Check by shaking the box to see if it moves,, if it does add more plastic bags !! It should not move when you shake it !! I have never lost a piece of glassware yet with this method !!
Forgot to say to wrap the object in one layer of bubble wrap before putting in the box !! Can even use recycled if you have it or buy at the dollar store !!
