What's a good price on a 83 ATC110?

Got a good friend with one and want to make him a fair deal. Think $300 is ok? He had the trike in the shop and got new coil, plug, carb rebuilt, etc. It's a good bike, but I'm cash strapped. I wanna make him a fair offer, but want it to be fair to me as well.
I'm really keen on swiping this ride. I never rode a 4 speed with dual range gearbox. Anyone give me some feedback on how useful the dual range is?
Thanks all,
Ff

[atc110]

i have a 1985 110 and the difference between high and low is amazing, it can go through anything in low and can go about 35 in high, but low is a little too low, and high's a little too high if you're running stock sprockets