looking for an apartment to rent

cattitude and I are moving again, and therefore looking for an apartment to rent. We need a place that allows cats and doesn't have a lot of stairs, and want 1200-1600 square feet, preferably near the 77 bus route (probably in Arlington, since Somerville or Cambridge would cost more).

We have our current apartment until the end of July, but would prefer to move into the new place July 1st or 15th rather than August 1st.

I would be grateful for pointers to either apartments for rent (I know this is a long shot) or real estate agents you think well of. We want to stay put for a few years, so even the best sublet isn't for us.

( other things we want )