Residential lease to own

For the last 3 years, I have been in a housing lease to own agreement with a large company. My lease contains a price at which I can buy the house at anytime. It has appreciated significantly over the last 3 years so there is quite a bit of equity. 
If I were to exercise my right to purchase and then sell the property, do I qualify for the exclusion on capital gains since I have occupied the property longer than 2 years? Or will I be taxed with short term capital gains?

Also, if I am taxed, can I count my 3 years of lease payments into my cost basis?