Only one was on the lease and she let her boyfriend move in years ago.

Is this a frequently used tactic?

To be exact, you need a broker on record and that broker needs to approve many transactions including signing the lease.

Three will be leased and in good good shape when the deal closes, two vacant and in need of repairs, which will bring the all-in cost, including rehab, to just a hair under market value.

She also said they haven’t resigned the lease yet, which i feel is a good thing.

I am getting a short-term lease while I get to know the city and save up some money.

I've run into issues where it's a such a hassle to call apartment buildings that don't answer and then refuse to talk to you unless you FAX over a signed lease, and doesn't always tell you much anyway.

This would be perfectly fine and something we recommend if a parent wants to 1031 into a house for a child - Make a lease, collect rent, declare income, and then gift back to the child if you really don't want to collect rent.It sounds like the way you've done it is a little fuzzier. 

I would like to lease out to an assisted living operator.

I know there may be a higher vacancy expectation due to summer months, but as far as I know most rentals in the area for college students start their leases in June and end in May the following year.