If the tenant is paying significantly below market rate, you could make a case for an increase, but ensure that it's fair and justifiable.Offer Renewal Incentives: Consider offering the current tenant an incentive to sign a new lease at a higher rate, like property improvements they value or services such as yard maintenance.Tenant Replacement: If the tenant decides to move due to the rent increase, be prepared to rehab the second unit and find a new tenant, ideally at a rent that reflects the current market rate.Remember, with long-standing tenants, especially those who are elderly or on a fixed income, it's crucial to balance business objectives with empathy and respect.

More properties, more problems, but if you have the funds to do it and cash flow is the only objective, this could be a good way to maximize your cash flow. 

The object is to get big enough that you need property management.

Recommend you do a lot of research on your own.I would recommend the following based on your post if these fit with your objective.  1.   

Pro's:  Can Buy a Deal with Minimal Cash Out of Pocket, then Sell via a Wrap Note or Lease Property Con's:  Due on Sale Clause, Overcoming Seller Objections, Many Moving Parts

I think that's very fair, and I can't see any judge objecting....

No system is perfect, so don't waste your time chasing after the next shiny object.

No system is perfect, so don't waste your time chasing after the next shiny object.

It's truly a gift that keeps on giving.Stay Objective and...

Honestly, in my opinion, there is not more powerful way to achieve objectives in life than writing them down and then sharing them as much as possible.I can't be much of a resource for you out in Califonia, but if you happen to decide that you want to invest in your old stomping grounds in Chicago we can most definitely be your boots on the ground!