Two terms I never fail to put into a lease, in writing of course, are as follows:
1) Owner(s) agree to have home/condo/unit professionally cleaned before tenant takes possession.
2) Owner(s) agree that if the tenant(s) renew lease after one year, owner will not increase rent by more than 2%/month.
Number one is pretty easy and widely accepted, but you'd be surprised by how many agents do not put this in the offer/lease.
#2 is more of a 'bone of contention'. I put it into every offer/lease that I write, residential or commercial, because G-d only knows what an owner will increase the rent by for the 2nd year and so on. I don't let tenants make offers without this protection. Usually it's accepted, but sometimes we have to fight for it or move to a slightly higher number. Most important is that it's addressed during the offer.
Boca Raton, FL