[RegularOpossum]

You're not building a museum so fractional specimens are the way to good. Teeth are a great place to start, they're ridiculously common (so affordable) and often of very little paleontological significance at this point (incredibly common). For fossil bones there, stuff like piece of Hadrosaurs that are again, so common they're of little significance.

For rounding out my collection of all the periods, I'm looking at fish and aquatic animals like trilobites.