hiring a scooter or motor cycle

Hi all...just trying to find out if anyone knows how easy it is to privately hire a scooter or small motorcycle (up to 250cc). I checked out some hire firms and was surpised at how expensive they were. A couple of years ago I was in Vietnam and it was possible to hire one privately for a weekend or few days at a very cheap rate. Any help greatly appreciated.

[StrykerGT2001]

Where exactly would you be renting? (which city). I know that the Let's Go guides list a few places where you can rent 200cc or so bikes, but most of them are outside of the DF.