I think if you want to do it cheap, then a handcrank, 4 rubber belt drives, and 4 screw legs would be the way to go. The problem would be making it look accept

I think if you want to do it cheap, then a handcrank, 4 rubber belt drives, and 4 screw legs would be the way to go. The problem would be making it look acceptable (either hide the mechanism, or display it prominently and make it look nice.