Tenant wants a loan for an a/c

[Kush Khandelwal]

The a/c in my unit broke down in my rental unit and it may take a week to get it fixed. 

The tenant wants to buy a portable a/c as currently it's hot in Atlanta.

They are requesting to buy 2 units from a nearby store and then return the units when the a/c is fixed. 

However they don't have cash or credit card available. They are asking if I can buy the units for them and they'll return in time.  What can I do to protect myself, to make sure they return the units in the required condition / timeframe to the store? 

Thanks

[Theresa Harris]

It is unethical to buy them, use them for a week or so and then return them.  I'd get them a portable one, but when the one in the unit is fixed, pick it up and take it to your house or you are unlikely to see it again.  How big is the apartment/house and does it need 2 portable units or is one unit enough (or can they move the unit)?