installing central air/ raising rents

[LuAnn Vigen]

My tenant is requesting central air be installed this summer.  We agreed to check into installing central air this spring when the sign the lease last fall, with the knowledge that the rent would increase if we did install central air.  I have a price quote for $3000.00 to have this done. My question is how much should I increase the rent to cover the cost, do I have them sign on for a 3 year lease. How would you handle this to be fair for everyone.