As it happens, I am 6'2" and about 185. I ride a 2006 dahon mariner I got on CL for a song. It's sizing and geometry are the same as the current speed and mariner, so I am confident when I say you will fit these just fine. I commute 8 miles a day on these kinds of bikes with moderate hills no problem. Unlike some folks here, I would recommend a bike with gears.

The dahon Eco c6 is in your price range, and I bought one for a raffle for my workplace and got to check it out closely, and it is a good bike for the price and will fit you just fine.

Hope this helps,
Warr