I’m also open to alternative strategies, such as private lending or passive investments in funds, to diversify and balance risk.Does this phased approach seem reasonable given the higher HELOC rate?

Not even Balance Sheet.I don't know if they changed their model since the change of subscription plan but it isn't ideal to use it as depreciation or amortization.They do have a balance sheet. 

I have seen many investors fail here because they only have 1 or 2 properties and when the downturns happen it kills them,  So you are going to need more money and more properties to balance out the ups and downs.Investing takes time, it doesn't happen overnight, and I think people fail to keep with it when it doesn't happen immediately.  

In today’s market most homes will be worth more than their outstanding loan balance unless they are VERY recent purchases with little to no money down.

However, from my research, it's extremely difficult to find any cities where the properties cash flow other than places like Cleveland which has its own set of drawbacks.

Trying to run a successful PMC is difficult but trying to run multiple companies - VR, Annual, cleaning, and landscaping is probably going to give you an aneurism.

"I'm willing to cancel the eviction so it doesn't reflect on your record if you vacate on x day and pay x toward your outstanding balance"Most tenants are unaware of the long-term consequences when they have an eviction on their record.

*The tiny, marginal benefit would come from how interest is calculated--average monthly balance vs balance on a particular day.

Use your HELOC to purchase the duplex outright for $118K.Your brother’s $50K down payment can immediately go toward reducing your HELOC balance, leaving a remaining balance of $68K.Create a formal lease-to-own agreement with your brother.

And the Solo-K would enable you to borrow $50K from the retirement balance to use as you please.