2000 camry tranmission screen

Was Toyota ATF fluid used on the flushes? Sometimes using non-toyota fluids can cause ATF to act abnormal. Older Toyota had replacable screen filter in trans, not sure on newer models. Not uncommon for trans not to have a replacable filter, earlier hondas did not have a replacement filter in ATF.

Yeah I had the post-warranty flushes done third-party, probably not Toyota fluid. I'm definitely going to have a flush done at the dealer.

I've read that there is a metal screen held on by 2 or 4 bolts, that can be removed and cleaned, and this should be done as part of a full transmission service. For what a dealer charges to do service, I want to be sure I get them to do everything, if it's applicable.

If you've been changing the fluid regularly that is all that is required. The metal screen in the transmission is not a "filter" designed to be replaced. Filter media is like what you find in an engine oil filter or air filter, the transmission screen is metal - if it gets clogged or restricted you've probably already damaged the transmission beyond repair for the debris to be that excessive. Just changing the fluid is sufficient. If you want to do something extra - probably also unnecessary, you can remove the pan, clean the magnets and replace the gasket, but again, if the fluid is clean you're fine.

On my older model it has a screen, you realy cant clean them since the dirt gets inside. Mine was slipping so I replaced it and it helped. You have concerns so have it done, then you can inspect its condition .