Need some thoughts on being diplomatic

[Loc R.]

I'm in final negotiations on a 4-plex that needs to be completely renovated.

3 units are vacant; the 4th one has a bedridden (as in 600 lbs) tenant.

There is no relationship between the seller and the tenant, but he would like to not leave her without shelter.

My offer will include language that all 4 units must be delivered vacant.

How would you guys handle this?