I'm in St Louis, so I don't know what your MLS has available in their datafields. Here, our MLS has a datafield for lease purchase, so we can search for homes that way. It's a relatively new field however, and many agents aren't use to it, so it isn't always filled out. We also see where a home may not start out as a lease purchase, but may later on become one, and they don't go back and fill out the field. As a consumer, typically you can't search by that field, only a realtor can, and then they can send you the results.
The other thing that we see here, is when a home hasn't sold, sometimes the sellers are willing to go into a lease purchase agreement (a lease option means that the buyer reserves the right to make a bid on the home at a later time - very few sellers are willing to accept a lease option contract since the buyer can walk away very easily. A lease purchase means that the buyer and seller have 2 accepted contracts - one for the buyer to lease the home for XX months at X rental rate and a second contract for the buyer to purchase the home on X date for X amount of money. That contract will have deadlines in it for when the building inspection and other contingencies need to be met. It may or may not have a portion of the rental fee or the deposit that is credited toward the purchase of the home. I'm working one now where the buyer will have been in the home for about 6 months before we close, but we did the building inspections and resolved them before the buyer moved in. The buyer had to have a valid loan preapproval letter when we wrote the contract as well. The only contingencies left are for loan commitment and the home to appraise right before closing and for the title and survey to be done and technically those could have been done earlier.