A typical 172 will give you around
1000 lb useful load, less 250 gall fuel so you are left with about 750
for passengers and baggage. Will that do it?

As you have probably already deduced, that should be 250 lb and not 250
gall

And some of the newer 172's actually have a lower useful load - more
like 850 - 900 lb.

--

Tony Roberts
PP-ASEL
VFR OTT
Night
Almost Instrument
Cessna 172H C-GICE