First,  
YES - I plan to reach out today to a real estate attorney. 

Looking for advice and if anyone has encountered this before just to get some preliminary data before making phone calls to lawyers. 

I have, under contract, a single family home that is a short sale.  The sale contract was fully signed and my agent was informed that the primary lender accepted the offer.  The offer more than covers the outstanding 1st lien, based upon what I've seen in the county mortgage records online. 
Closing day came and went - and then suddenly a day or two after the closing date was to occur I receive notice that the seller "needs to send a cancellation notice, as there is suddenly a 2nd lien who won't agree to the sale."  
Rumor is that the 2nd lien is a general contractor, but I find zero record of this in the county websites.  

I've already paid for liability and flood insurance (had to be paid before close, I paid it 24 hours before the closing date) and now I'm being asked to sign a document basically mutually agreeing to cancel the sale.  I'll now need to fight to get the insurance cancelled and refunded, and something just seems very fishy about this whole situation.  
I do not understand the following: 

- How can there suddenly be a 2nd lien, with no evidence of such on the county websites, and how could the seller have agreed to the sale and executed the sale contract fully to begin with, stating that the short sale was accepted a month ago if he had evidence of this second lien?  

- Doesn't the execution of the sale contract bind the seller to sell me this property?  Once he signed and accepted this offer - he can't suddenly decide that he needs more money to close out a 2nd lien.  If that were the case -   he should have never accepted the offer to begin with, correct?  In FL law, there are only certain reasons why a seller can cancel a contract (buyer can't get financing, force majeure, mutual agreement of both parties, title issues, etc)

- Can this 2nd position lien holder prevent the sale of the property, even though the sale was allegedly agreed upon by the primary lien holder?  Again - I see no evidence of a 2nd lien in the county websites, but apparently its a G.C. who did work on the home. 

- Can I still force this sale or somehow recover damages from this seller?  I'm certain I won't get every penny of my insurance payment back (had to pay 6 months in advance), I've had GCs and builders out to the space to give quotes, I did a sewer line camera inspection, etc. 
I know some of this is the cost of doing business as a real estate investor (sewer main inspection, for instance) - so I'm not concerned about that.  I' m more concerned with the $2400 in insurance costs, the seemingly fishy way this is all going down, and the lack of transparency around this sudden "2nd lien".  

I also plan to call the title company this am and see what info they have.  

Does anyone have any suggestions, information, tips, etc? 

Thanks!!