Hi,

Janet gave you good sound advice. Everthing needs to be spelled out in writing including all of the "what ifs.
Normally, in this situation you would be paying higher than the goiing rate for the rental with the excess credited back to you at settlement. What happens to this money if you are unable to settle? Very important to address this and all other what ifs in the contract. You need a very experienced realtor and possibly a real estate attorney.

It depends on how the agreement is written. It is entirely possible that if the agreement is written to the seller/owners advantage they could keep the moneys paid if you are unable to buy the house at the end of the specified time or if the buyer is unable to uphold his/her side of the agreement. Read everything before signing ask questions and get an experienced attorney or a Realtor with property management experience to read it with you. In these situations you need to be sure there is a " what will happen if" for everything that you agree to.

I hope this answers your question. Thanks for using Trulia.
-Janet