Mark writes:

Lessee, I've a 172 with 2 pax and overnight gear out of a 1200 ft
runway in light winds, only mogas available locally but I'm flying
over water and filed for 6500 in case I have to climb over some
weather en route. Avgas is available at a regional airport en route
but possibility of that field being closed to VFR and Avgas costs so
much these days. Do I fill up or not? Not so clear cut when it isn't
a sim.

Do you have a method, or do you roll dice?