Should the inspection concludes that the property possesses fundamental flaws which renders the property Inhabitable and /or the repair costs of those flaws would equal or accede the sale price of the property, the Purchaser then reserves the right to remove himself and all his obligations of this contract and the seller agrees to refund the earnest money to the Purchaser in full."

You can steal real estate legally through adverse possession (personally I don't do that).

The option does not give the right of possession a seperarte lease agreement does.

If so, before or after the new owner takes possession of the Title? 

For example if ur lease expires in 3 months and they want to stay for 6 months, you can make a case of terminating the existing and doing a new 6 month lease is best for both parties.Even without a new lease, one might consider a detailed inspection of the property conditions so you know at least what's broken or damaged at the time of your taking possession.

The Seller In Possession (C.A.R. form SIP) form is like a lease as it has a definitive termination date.

You would have "landlord" insurance on the property, then you would also have tenants insurance on the possessions in your unit.There is a good chance this could be handled differently in Florida.

How hard will it be to get rid of the occupants once I get possession of the property?

When we first took possession of our space I fell in love with a beautiful, but dilapidated 1912 Craftsman that had been unoccupied for 2 years. 

Sorry to hear about your problem.DC 100c, Notice to Quit to Recover Possession of Property is the correct form.