I have a folding one you can get at wall mart.  Hang a bag on it and  tie
up the bag and toss it when you are done'  I don't use it often but it
stores away and you can leave it set up and ready when you anticipate the  need.
I used to have a metal frame on that I lost in the garage, the new  ones
are plastic.  Cheap and simple and with a cover it can double as a  table.

Pat