Like many (most) businesses it requires an investment of capital; money expenditure for ongoing marketing; management of operating, marketing and professional personnel; keeping accounting records and filing tax returns; established sales practices; constant monitoring of goals, budgets, and productivity; establishment and implementation of operational systems; and providing customer service.  

They may have a separate system or entity that is used for holding properties vs the business itself for legal protection.

The GIS map designates it as a single-family dwelling, but the property is clearly set up as two units, with separate HVAC, electrical systems, etc.My main question is: Would it be possible to obtain a permit to legally convert it into a two-unit property?

We have a Propritiatory Property Launch Program to sell houses really fast 4034 Manchester Rd Akron , Days on Market 341 (lightning fast proprietary system) I think I will keep my non proprietary system, we are under 30dom market average the past four years same area) 2284 Bailey Rd Cuyahoga Falls, Days on Market 221 (hate to see what his DOM was before he figured out his proprietary system)Yeah, sounds like you are good with whatever "non proprietary system" you are using.

This will help you to build your systems out as well.

Quote from @James McGovern:One of the problems with the new system is no transparency, so will be tough to know if commissions were negotiated?

Get an STR property management system like Hospitable to help automate a lot of things.

Now for the next hiccup, spoke with the health department today, they are saying the entire septic system will need to be replaced because of a change of use.

Not because it has broken but to improve stuff.Either way an older home requires more maintenance than a newer build until those systems that wear out are replaced (like the heating/AC)We are 7+ hours from our lake house and we self manage it just fine and have been for the last 6 years.Regarding the LLC, will you be paying all cash for the property?

For Example, my Note Investing notebook has Sub Categories for Consolidated Note Resources, Goals, Note Buying Criteria, Foreclosure Timelines and Costs, State Specific Notes, Systems for The Note Business, Collection Time Tables, Note Conferences, Bankruptcy in Notes..