I would like to know after the contracts are signed and done. How do I determine what the rents going to be. I’m new in doing the real estate investment.
Well, you should know before you sign 
Now you said “rent”. Rent and lease with an option are two different things. Rent can be lower or higher than a lease and it goes by what the market rate it. I would go to Realtor.com for example and look at the properties for rent in that area and what others are charging for them as an example.
Lease option on the other hand would need to cover the mortgage payments. Charge them what they would have to pay if they took a loan from you. Use an amortization table and calculate it then add insurance and tax to the payment.
Thank you for letting me know what the difference is in Renting and Leasing. How do I go about finding Private Investors to invest in my wholesaling project so that I can move on further.
So you are looking for investors to wholesale to? I would start by joining the local investor association, post your wholesale deals on rehablist.com, and calling the “we buy houses” ads in the paper to find out if any of them looking for wholesalers.
Newspaper, property management companies, other investors from a local REIC, etc.