One form of that is finding a specific niche subject matter expertise...something like an ice fishing cabin that those of us who don't know a thing about the category would never think of investing in.

I recommend you consult with a lender with expertise in investing, preferably someone local to you, to discuss the lending options best suited for your goals, strategy, and tactics.

Engage in networking, social media, on line forums, associations, etc and showcase your expertise.3.

@Heidi FahringerReal Estate Expertise - Are they familiar with real estate-specific tax strategies, such as depreciation, 1031 exchanges, and write-offs for repairs, property management, etc.?

Just by the knowledge, expertise, guidance, and support of a group you are connected to?

Expertise and Experience: Property managers have specialized knowledge in managing properties, including understanding local market trends, legal requirements, and tenant relations.

Second, that their money was invested in highly speculative start up business deals that the sponsors had no background or expertise in.  

We hire the architect for his expertise on the most efficient planning of the building.

If they're located two or more counties away, their expertise in the local market may be limited.

A good EA or CPA will charge for their expertise, and it’s usually not cheap.