I also highly recommend you work with a real estate professional to find your next rental and have them research the home you would like to rent. If you can find one that someone recently purchased you should be in good shape and if they paid cash even better. Your real estate agent can research this for you so you don't end up in this situation again.
If this is such an inconvenience for you it may be time to move or see about purchasing the property yourself.
Please consult a lawyer regarding the landlord's right to access the property.
And, my advice is that in the future, you use a qualified Realtor for your rental needs who can access property records to see if the landlord is likely to slip into short sale or foreclosure. If you did use a Realtor, please call them - unless they're the listing agent and could have a conflict of interest.
What a mess, I'm very sorry for your situation. The answer is, you can probably sue anyone for anything, but winning a suit and getting damages is always another matter. Only a local attorney who works in this area can tell you what your odds of success are. Chances are, where it's a short sale they won't have much to get from them if you win. You may have other choices however, so find a good attorney and see what they suggest.