Will these covers work with my factory keyless entry, or do I need the keyhole?

These covers feature a factory keyhole cutout, so the mechanical key access remains functional. If your Xterra uses keyless entry exclusively, the keyhole will simply be an unused port—it won't interfere with locking or unlocking.

Do these require any adhesive, fasteners, or prep before installation?

Mounting method and hardware are not specified—test-fit them first to confirm attachment points, then decide whether you need adhesive, fasteners, or clips based on how they align with your door handle structure.

Can I paint these covers, or do they come pre-finished?

These ship pre-finished and ready to install. If you want a different color, light scuff and prime before painting; refer to your paint supplier's prep guidelines for plastic panel work.