I don't believe in "cheapo" bikes, say a $ 50.00 used, beat up bike. If you're gonna spend plenty of riding time
back and forth from work, might as well invest in something a little decent. I just invested in a Volpe for example at $ 530.00, enough gears for my hilly area, plus decent quality to give me a decent ride. In my case I don't have to worry about parking 'cause I can park it inside the building, very securely.
A light touring, cyclocross seems to be the way to go, then again it all depends on your distance and type of riding....mine 12 miles each way.
Corsaire