1. Your lease is good until the end of your lease agreement (so it it ends in January 2013 for example, your lease can't be changed even by the new owner), unless specifically stated that the lease changes if it is sold.
2. Once it does sell, the showings will stop. After it is sold, there are a few more inspections, but you won't have a lot of traffic in your home.
Now would be a great time to meet with a real estate professional and see if you can not own a home for less than you are currently paying in rent. Really, I am serious, many renters have not calculated the real benefit to them of the extremely low mortgage interest rates readily available.
Best of success to you,
Annette Lawrence, Broker/Associate
Remax Realtec Group, Palm Harbor, FL
727.420.4041 - http://www.RealEstateMadeEZ.us
I don't give my tenants an option, but some leases will allow tenants to 'opt-out' of allowing showings for a fee of one months rent. As already stated, read your lease.
Understand, though, that the lease will run its full course even if he sells, so long as you're complying with its terms and conditions. So let's say you're current on payments, taking care of the property, etc. And let's say the lease expires January 1, 2013. He can sell the property--that's his right--but the new owner must comply with the lease, too. That means you can't be kicked out early just because the owner sells the property.
Again, read the lease. And, if appropriate, check with a lawyer.
Hope that helps.