I just got off the phone with a home owner who has gone the last two years thinking she wouldn't benefit from refinancing her home. She was literally exstatic after finding out that her monthly mortgage payments would decrease by $1,000 a month. All it took her was a phone call and a little paperwork. (She has owned it for 15 years, has no trouble making the payments, etc.)
She has rental properties as well. So she called about one of them… her payments went down $900.
Even if you bought two years ago, make the call to your lender and ask about refinancing. Call me if you have questions, it really is worth your time!