I paid various prices for them and I got them directly from Japan at various times in the late 90s and early 2000s.
Here are some examples of a few that I have:
This one is Vegeta from Dragonball GT in mid transformation to SSJ4:
These three are as follows starting from the bottom going up: Trunks from Dragonball GT with original sketch underneath cel, Adult Gohan from the Origin of Trunks film with original sketch underneath, Child Trunks from Origins of Trunks film with original sketch underneath
The next three are as follows starting from the bottom going up: Vegeta from Buu Saga with sketch, Super Saiyan Goku fighting Freeza with sketch underneath, Goku, Pan and Trunks from Dragonball GT with sketch.
The next three: SSJ4 Goku from Dragonball GT full cel with background cel underneath, Goten from Dragonball GT full cel with background cel, Gohan from Cell Saga with sketch underneath.
The next three: Krillin, Trunks and Gohan from the Cell Saga, Goku, Krillin and Gohan from Freeza saga, Trunks from Cell saga with Android 19's arm.