For that short distance, a 20" wheeled single speed from Dahon or Tern would work well .. Mu Uno, Link Uno, Verge Uno, Speed Uno .. all good fold-in-half bikes that are simple and ride well.. with the Mu or Verge, you could add a belt drive down the rode if desired (I did with a Mu) .. all the bikes listed above will take a SRAM 2 speed easily if you felt you needed another gear.. also, keep an eye out on your local Craigs List .. lots of bikes will get the job done, but if it were me, I'd keep it as simple as possible.