I am also looking for tax optimization as the business will require cash reserves and is a high risk business from a liability perspective.

Helps with your debt to income, better opportunities at cash flow, and typically requires less down to purchase.In regards to challenges, I usually build in an extra 10-15% to deal with things that I can't see behind the walls, including dry rot, electrical or plumbing issues, etc.

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.

Real estate investing requires a good deal of research, so build your arsenal and over time you'll be an old pro. 

It may not be required, but we are generally in a better place to absorb the loss than our tenants.

Scaling up properties requires cash flow or equity, continuous education, networking, mentorship, patience, and persistence.

The 8 unit has required more time and energy because it had been poorly managed for years.

Is there any sort of requirements for the student to be accepted into the program or does the 8K make you automatically accepted? 

Ask your lender about their recast requirements (payment amount and frequency).

If you get a quote significantly below the numbers above you need to ensure that the contractor will actually execute the work and perform it to the required standard.