My goal is to achieve enough cashflow to be able to semi-retire from a highly lucrative W2 job and focus on business ( both in real estate and non-RE) more fulltime.

I am highly motivated and obsessed as of late to achieving these goals.

This could be a strong motivator for them returning to work of some sort.

It's going to be hard to achieve the appreciation rates of years past when growing supply at 3-4% per year.  

The primary motivation to sell now is the constantly anti-landlord policies in Alameda county and fear of getting stuck with tenants who do not pay and who we cannot evict. 

Seller was extremely motivated.

There are lots ways to find motivated sellers and off market deals. 

So, in order to get down to the real meat and potatoes of that person's life you're going to have to work on building rapport and discerning their needs or motivations. 

Ultimately I think this is a sound way to go and drafting a lease from the ground up seems like needless rework.The key things you want your lease to be are:  compliant with your local Landlord Tenant Act rules  Enforceable I'd go with the simplest solution to achieving that.

This will help you to stay in track and achieve results.