I'd bet any local University has classes applicable to commercial RE investing and management, audit the course instead of attending for a grade, much cheaper

Our Grade A materials have 2 yrs of light use.

What's your experience level managing large-scale multifamily?

Diversification is the only protection for Black Swan, large scale negative events. but can this happen again, Absolutely.

I’ve scaled to 9 doors across those markets and so far so good.

What strategies are you focusing on to scale your rental portfolio?

There is no hard grading system on investment properties so “Class D” would be a subjective term but ideally it would refer to the “state/condition” of the property, “quality/affordability” of the tenant base and the “rent/income” it could provide.  

For that reason, in the medium-to-long term I like the idea of multifamily residential for the more aggressive depreciation and ability to scale (vs single family). 

Wanting to scale quickly I've thought about doing a cash out refinance on the investment property after about a year and using that cash to pay off the HELOC then using the HELOC once again to get in the next property (rinse and repeat).

This is particularly important as I prefer to self-manage properties, and accurate cost estimations are crucial for maintaining profitability.Scalability: These rules help in maintaining a consistent evaluation metric across multiple properties and markets, aiding in scaling my portfolio systematically.That said, I understand that each investment should be evaluated on its own merits and that these rules may not capture the full picture.