You can get a basic Ender 3 printer for around $100 if you look for deals (Microcenter has a coupon if they have a store near you, or look for used). After that it’s just purchasing filament which is $15-$30 per spool depending on the type and quality. Typically a 1kg spool has about 300 meters of filament. PLA filament is typically the cheapest and most beginner friendly. It works for most things but will sag/deform in hot environments (car interiors, direct sun, etc.).
I use a screen protector and case. I tend to drop and scratch phones so it’s for the best. No protection plan though. I should replace the screen protector as it started peeling on one corner a few months back.