The price will not be a function of the number of gears - WalMart has bikes with lots of gears. It is a function of the age, quality level, condition, etc., of the bike and the quality level of the "gruppo." 16" mtn bike sounds about right for you. I would suggest you take a chance on one of those "I like to fix up bikes" CL ads, given all the previous discussions re: your bicycles and your reluctance at this time to make a commitment.