Give some thought to where you will be in 5 years, and that will tell you a lot.
I think your instincts about the commerical litigation job are probably spot on, given the extra pay and the better future job prospects.
You should also consider office environment before making the final commitment. Now that they have made a firm offer, perhaps it is time to tour the place and talk to people who actually work there, if you haven't done so already.
A jeans environment with little overtime that gives generous paid vacation, might not pay as well in gross dollars, but would allow you to go to night school and/or pursue other things that make you happy or more successful in the long run.
You could also go back to the real estate law firm and try to renegotiate a higher offer, if it is something you might be interested in, but the money is holding you back.
I hope this helps a bit.