It depends how low your score is. The other thing to consider is, if you find a lender who is willing to "take a chance" - they are most likely going to charge you a very high interest rate for the perceived risk involved on their side.
Rent to own, on the other hand, has a high potential to turn into a giant mess - and it laden with pitfalls for the buyer. There is unfortunately no easy way to purchase a home without good credit and sufficient income - although everyone is looking for one. "Rent to own" is not what it sounds like - you basically "rent to save up a sizable down payment" - then still have to qualify for the financing at a later date.
If you go the "rent to own" route" - you'll typically have to pay a large sum of money in the form of an option upfront to get things started. Plan on $3000-$5000. Next, you'll agree to a price, without knowing where the market is going to be when it's time to exercise the option to purchase. You'll still have to qualify for a loan at that time, without knowing what your credit situation will be. Additionally, you are typically responsible for all repairs and maintenance of the property throughout the lease - since you are technically buying the property when it expires. Throughout the lease, you'll get a small portion of your monthly rent credited towards your down payment.
If you pay the rent late, can't qualify for the financing when it's time to, decide the house no longer fits your needs, or decide to ultimately back out of the deal a year later due to circumstances that you couldn't have planned for - you lose everything (your initial deposit, and all credits paid over the life of the lease).
I have talked with lots of people who are somehow under the impression that "rent to own" simply means that you pay the monthly rent until you own the property - without having to qualify for anything, or use a lender. Nothing could be further from the truth.
While there is no shortage of agents who will be happy to sell you one - my advice is to focus your time, money, and energy into repairing your credit or finances, and purchase a home using traditional means.
Yes it means you'll have to wait a little longer - however it's one of the biggest financial decisions you'll ever make, and it will likely have some effect on everything you do in the future. Take your time and do it the right way.