Establish an operating agreement for each LLC.

Having said that, before you dismiss a sponsor for violating this guideline, take some steps to ensure you are communicating with the right person, and that communication is actually established.

Either would be a great option; I'd probably choose Roseville because it's more established, but the City of Elk Grove deserves a lot of credit for its impactful growth programs, so it wouldn't be a bad option. 

NOTE:  there may be some tax on interest or principal on the payments--seek professional advice.Also, stress there will be no inspections or other contingencies--sell the 'peace of mind' side of the equation.You have known each other for 12 years and you established you are a great payer. 

The best way to build relationships with cash buyers is to establish yourself as an authority in this space.

Establish a Charitable Remainder Trust (CRT): By placing the property into a CRT, you can receive a charitable deduction, defer capital gains taxes, and receive income from the trust.

I've seen investors allocate 5-10% for capital expenditures (capex) and vacancy, but you won't have a clear understanding until you've owned the property for a few years and established a track record.

Establishing a relationship with a few of them locally or nationally [if you have a network] would be extremely beneficial.

Once i have the network established, I might consider STR in future.

A few days ago I visited an off market property in Austin in a well established neighborhood if interested feel free to connect.