3 weeks ago we found our dream 1 week vacation rental in Florida. We contacted the owner and sent in our deposit. Everything was done through well documented emails per her request. Yesterday she sent me an email stating that she has sold the condo and will be returning our check that she didn't cash (also documented in the email). Can she do this? I live in Texas. We have secured a new reservation by the grace of God since this is the busiest time in PCB, FL. But there is a $500 price difference that she refused to help pay for. Is there anything I can do?

What written terms were there about either side cancelling.

You need to look at the contract. If you have any rights they will be spelled out there.

If she refuses to do anything you would have to take her to court and I'm not sure you would win.

You need to look at the contract. If you have any rights they will be spelled out there.

If she refuses to do anything you would have to take her to court and I'm not sure you would win.

Certainly, nothing in life is an absolute certainty, but it appears to me that OP has a good case. There was a written contract. OP paid the deposit called for in that contract. Then the other party breached. It looks to be a good case, unless I am missing something.