Sounds like you may want to partner with somebody that’s more experienced or find a mentor.

Non-passive to achieve this level of return.Add the addition of the ADU makes the main unit rent controlled if over 15 years old.the work to add an ADU likely exceeds the effort of a brrrr that can achieve infinite return  Experienced investors are adding multiple ADUs by leveraging items like bonus density, committing units to affordable housing, etc.  

It is maybe a couple thousand dollar up-front cost for the developers to determine the viability of a project.I work with experienced developers, who could perform & gather all this data on their own if they really wanted to, but the value that an engineer brings on these is typically worth their time & small cost. 

I'm eager to learn from experienced investors and gain valuable insights into the world of STRs.

Quote from @Chris Seveney: @Charlene Kingsnorth have you had an sec attorney also review what you are doing as if you're are having multiple people as part of a loan participating in it depending on the state this could get you in hot water - so be careful  good point Chris some state allow fractionalized deed of Trust mortgages other do not or require PPM like documents prior to offering them..

And I an experienced 2-4 unit investor here as well, and have self managed for the most part.  

Consulting with an experienced eviction attorney in Seattle is essential to confirm their status and to ensure you’re following the correct legal process for removing them, if necessary.Disclaimer: I am not an attorney or an eviction specialist, so this is not legal advice.

Quote from @Brandon Weis: In your opinion, as you are starting out at 0 reviews, do you think it is a must to beat the competition on price to overcome customer's hesitancy or lack of trust with no reviews?

I experienced the same thing when I had a small portfolio of small SFH, duplexes and triplexes.

They’re usually a goldmine for networking and connecting with experienced investors in your area.