To lease or not to lease

[Anthony LaGuardia]

I just bought a duplex a couple of months ago where both units were occupied by friends of the seller. Neither had written leases and I was told that they are on month to month verbal leases. The people are older and have been there for 3 years with no issue. I moved in upstairs and started renovations. My problem here is that the people down stairs have mentioned leaving because the stairs are becoming to much for them to handle. I'm nervous that if I issue a lease for them to sign it will make them want to leave even sooner and all of my money is tied up in my renovation of the upstairs. If the unit down stairs turns over I will need to put thousands into it to make it rentable to the market I am trying to appeal to. Given the risk of pushing them out he door what should I do? Anthony