A "lake house" might be in a residential zoned area where a commercial use would be prohibited or at least require a variance (approval) to make an exception.

@Steve Meyers I’ve been running this with some success with a local cincinnati agent on 2+ units and nationally with a commercial broker for shopping centers.

Or to avoid angering you they charge your tenant's huge commercial fee's so you can forget about retention.

If you don't flip, these guys are usually in the appropriate isles at Home Depot with the carts of supplies or just hang around the commercial check out.

It is not very difficult or complicated to evaluate commercial real estate, there are plenty of good books available that can teach you how, textbooks, online courses, community college classes, even excellent youtube videos etc, and it is actually quite enjoyable in the process to learn.

The second case was a commercial property (an 8 unit multifamily in a complex of 6 individual 8 unit buildings), owned by a group of investors.

What kind of commercial building is it? 

I have a few commercial loans that don't report to my personal credit. 

My 2 cents: You're young, you could get a real estate or real estate adjacent 9-5 so you can get paid to to learn more about real estate while learning and building the side hustle outside of business hours.Seems like you live in a major US market so that's a plus, you could get a tenant services coordinator job in commercial real estate making $40-60k (not sure if that's more or less than what you are making now) It's an Entry level role, anyone with a degree and a polished resume and a passion for real estate should have a decent shot at landing a job like this.

For active investments I advocate considering how you can diversify WITHOUT ceding your competitive advantage nor the superior profitability of the niche your in.As an example my business is running an investment fund and syndication high interest commercial mortgage loans secured by income producing real estate.