Put it on the water and leak test. Check all switches, pumps, nav lights, etc.. I would not be concerned with speedometer or trim gauage not working. Speedo is not worth having and trim guage is easily fixable, they do tend to fail a lot. I elected not to repair mine last time it failed. You can feel the sweet spot when trimming up and with some seat time you will hear when you are trimmed to high. Inspect the transom for cracks, and crawl under and inspect the hull. Scratches are normal, patches and repairs are not. Lots of guys on here will have even more detailed information to add. I would take a meter and see if the charging system is working while the motor is running. It should read 13.5 -14.5 depending on motor rpm. Would not be a bad idea to drain the lower unit and check color of oil and for metal. If oil is milky, you have water in the lower unit which means a seal is leaking. Good luck!