Yeah I see why people like the cheap ones, but ngl I always mess up the installation if it doesnt have a good frame. Since youre willing to spend up to $30, I think you should check out the Spigen Glas.tR EZ Fit Glass Screen Protector. It usually comes in a two-pack for like $17 and the tray makes it basically foolproof to get it straight without dust getting trapped underneath. I tried a super cheap brand last time and it was a total nightmare with bubbles lol. Another one I keep seeing in my research is the amFilm OneTouch Tempered Glass Screen Protector. Its also pretty affordable and has a similar easy install tool. Do you think its better to get a single premium one or a multi-pack just in case? I personally feel like having a spare is a lifesaver for when you inevitably drop the phone and the protector cracks.

Consider tempered glass; check oleophobic coating specs. ESR's decent, often under $20, good hardness rating.