Seller wants to do rent to own without me

My friend, who I’ve known for three decades, wants to do a lease with an option to purchase with his home. There are other factors, but I want to stick with the legal.
My friend doesn’t have much equity and he is set on doing “rent to own” because of the non-refundable option fee. So frame your answers around being price sensitive

Questions:

Where can my friend find an “Option to Purchase” contract? Rocket Lawyer?
Is there a less expensive place to sign the agreement other than a lawyer’s office?

He wants a place to sign other than his residence to give it an air of legitimacy. If a lawyer is the best place then:

How do you find a real estate lawyer who knows rent to own?

There are other questions, but I feel I’m pushing it.