1st Deal-How would you work this for a rent to own?

I hope this is not to vague, but I am looking to do my first rent to own deal. I would like some suggestions on what some seasoned and experienced investors would do.
Length of the contract(2-5 years?)
Downpayment to charge renters
Monthly Payments to charge renters
Anything else I could be forgetting
How much to increase the interest every year?

House is appraised at 185,000
Bought for 145,000 fully rehabbed and no work is needed