Virtually all Tier 1 brand panels have 25 year production / performance warranties to deliver 80 to 85% of the original level of power at the 25 year mark.
What the OP mentions is a fairly typical grid tied setup; with these, the CFE solar meter is bi-directional and records values for both "use" and "sent". Both appear on the bills, and the user pays only the "net" difference (or has a 12 month rolling kWh credit, if production is higher than use).
Maintenance - panel cleaning several times per year in the dry season is recommended, plus an inexpensive PM check of the system each couple of years, to check and adjust as needed, the support structure, roof connections, panel mounts, wiring harnesses, ties, and connections, and the inverter condition and performance (and inside cleaning, if a central / string inverter).