There are fewer rent to own properties in the current market. With historic low interest rates, an $8k first time buyer credit, and mortgage programs with as little as 3.5% down, sellers have little reason to rent if their goal is to sell. Generally, a seller will look for a significant down payment to be escrowed when structuring a rent to own purchase. So if you have a deposit, the next issue is the ability to secure a mortgage. If you are unable to secure a mortgage today, but expect to be able to in the future, that's another concern to a seller.
Having said all that, it is possible to search the MLS for properties where; the seller will participate in financing, there is a lease option, or the mortgage is assumable. Currently there are no properties in Whitman or East Bridgewater that meet that criteria. If you'd like me to notify you if anything becomes available please feel free to contact me.