During this time you are not generating any return from the money invested in the ADU.

I know there are a lot of very experienced investors here in the country who have been successful for a generation or so.

Is 10% ($1,750) per month in simple, taxable, spendable interest very attractive after owning real estate that likely did not generate that kind of cash flow? 

Typically, if they can make it work as an STR they go that route because it almost always generates the most revenue.

The property alone is worth a million but is generating an estimated $250k/ yr with the ability to add 3 units on site and acquire an additional 13 acres.

Then I sit down with a spreadsheet and analyze all parcels for an area and generate a list of target properties right from my computer.  

You will then use the K-1 generated to prepare your tax return. 

Accessory Dwelling Units (ADUs) are an increasingly popular way to generate additional rental income on an existing property.

I have three listings, 1. unit with a pool and hot tub, 2. unit with a hot tub, 3. both units together as a 12 sleeper.Gross monthly income (after booking channel fees) for the first unit over a 7 month period was $7309.Gross monthly income for both units over a 14 month period is $11,297 (after booking channel fees) As a long term rental the combined rent would be in the region of $5500.Is it possible to sell the property based on the income generated by the STR business or would the value always be based on bricks and mortar comps? 

The experience was really bad as I was getting 1-2 year old leads to cold call that I knew had a 0% success rate and I do much better generating leads organically on my own.