Set your expectations before the first spin
Deciding how long to play starts with one fact: nobody can say when the bonus round will come. Free spins start when LIGHTNING or SCATTER symbols land, and no earlier spin predicts the next one. The result of one session is random, whatever the RTP figure says.
Comparing RTP versions begins in the game rules, the only place that shows which version is running. Neospin Casino lists the RTP version of Frightening Frankie there, so check it before you stake. Each version pays back a different share, so the rules tell you which one you are playing.
Planning around the top prize means reading it as a ceiling, not a target. Frightening Frankie stops paying at 2,800x the bet, and that cap is reached very rarely. The Monster Trail round also ends the moment that cap is reached.