Hi Bob,
Here's a search of the IceInSpace Classified archives for prior sales listings your main show pony, the Meade LX200 12. It should point you in the right direction. Just be aware of date of sale too...
Meade LX200 12 Classified Archives Search
Having a look through those listings suggests something like $2100 to 2600 for the LX200 12
Best
JA