Servicing a certified '04...?

The MAINT REQD light will flash briefly, starting 4,500 miles after the odometer timer was reset. That light will appear solid, starting 5,000 miles after the odometer timer was reset.

You could change the engine oil/oil filter yourself and reset the timer. Instructions are in your owner's manual or you can do a search.

The main service that I would suggest include:

1. Replace engine oil and oil filter
2. Check engine and cabin air filters, replace if needed
3. Replace transaxle ATF fluid, not listed in the maintenance schedule but this is a good preventive maintenance practice

Take a look at the 75K mile maintenance schedule within the warranty and maintenance guide, you'll see there are a number of inspections required. Since your car is certified I think it is reasonable to assume those inspections had been performed prior to your purchase.

 

If you don't have Toyota's Scheduled Maintenance Guide see here:
Toyota Parts and Service

If you don't have the Owner's Manual, buy one from a dealer or online. It's filled with info every owner needs to know.