Roselady,
I have two personal floor frames. The first is 30"round and I beleive made by Hintenburg. I bought it at a quilt shop. You have to baste the quilt to use this frame. It has a single leg in the middle and rotates. I find that I tend to overextend my arms when using it unless I force myself to rotate more often. I sit in a wing chair to use it.
My second one I ordered at a national quitl show from Grace. It is 24" and square with rounded corners. It has a single base that has an arm that extends sideways from the base and then the hoop rotates. I find I have a problem with the bulk of the quilt that is not in the hoop getting caught on the arm when I go to rotate. It does have a built in extension light that is nice and was free since I purchased it at the show. Both hoops have their advantages and disadvantages. I usually have a dozen or more needles going at the same time. I stitch as far as I can reach with the first one and then go on to the next until the whole hooped surface is quilted. Then I unhoop and move the quilt to where I continue the lines I started.
Both hoops were in the $100 range and I have had them both for a while.
Good luck