Thanks for using JustAnswer. It is very difficult to make dentures fit when there is no bone left for the denture to fit on. A denture needs bone in order to stay in place. Without it, the denture moves around and cannot be stabilized. I know the cost of implants are expensive, but check into mini implants, they are less expensive and work well for your case. Without doing something to stabilize the denture, it will be hard to have one made that fits and works right. As far as the appearance not being right, could be a case where your lower jaw is further back than normal. This usually gives the sunken in appearance. If there has been several sets made and they keep looking the same, this could be the case.
I will be glad to respond if needed.
Best of Luck!