You can do bodyweight rows if you have a low bar or even using a table. Way back before I even set foot in a gym I built strength at home doing press ups, pulls ups/chin ups (using a door frame bar), rows using a table and dips using the back of two chairs.
I think the best is to use gymnastics rings. They aren't expensive, but you do need to attach something solid to the ceiling to connect them to (I use a piece of iron angle painted white, lagged screwed into ceiling joists). The straps are quickly adjustable and you can do a bunch of pulling exercises, including the rows. The real advantage of the rings is that they allow your wrists and elbows to change angle through the pull path which can greatly reduce the stress on the joints and feel more natural too.
