Like rent, security deposit, lawn care, snow removal... compare this information to the actual leases and what the seller says. 

Most of the time you will need a earnest money deposit, which can be anywhere from $1000 to $10,000 (I did that for my last cash offer).

My closing attorney wants to walk away from this Fannie Mae Foreclosure property, get my deposit back and forget it.

My question is does anyone think I should pursue the entire deposit via litigation? 

Typically the seller will provide a check for deposits plus interest and prorated rent collected at closing (separate from title company funds).

. $36.00 (36%) of that gets withheld by Airbnb and you get a net of $64.00 deposited into your US bank account.

Be clear about what you expect, with a written lease, rules for the house, and a deposit.

The vast majority of lawsuits against Landlords are for wrongful eviction, security deposit disputes, and Fair Housing Violations.

Ask the seller to reach out to the tenants and let them know the building has sold and the current leases will be honored and deposits transferred to you. 

For example, Name Removed - real estate salesperson license (476-381650) placed on probation for two years and fined $2,500 for acting outside the scope of his salesperson license, specifically owning and operating two web sites, engaged in leasing condominium apartment units, held security deposits without an escrow account and co-mingled funds with his personal accounts.