Royal Foam Dev

I've been struggling to figure out the right stroke length for a linear actuator I want to use in a fold-down bed mechanism in my van conversion. The space is really tight, and I'm worried I might miscalculate and end up with a system that jams or doesn’t extend fully. I’m considering a 12-inch stroke, but I’ve seen some people use 6 or even 20 depending on their setup do you guys consider when choosing stroke length?