Do I need fasteners to install this, or does it come with hardware?

Hardware is not included with the handle. You'll need to source bolts or screws that match your factory mounting points—check your original handle or service manual for the correct spec and size.

Will this fit both driver and passenger side doors?

This is a right-side handle only. It works as either driver or passenger pull depending on which door you're installing it on, but you cannot use it on the left side.

Does this need paint or prep before installation?

The handle arrives ready to install as-is. If you want to match interior trim color or finish, prep and paint before mounting to the door panel.