We bought a single family up here last year and converted a garage to an ADU, which rented out really quickly to a great young couple.

Helps you stand apart from similar 4 bedroom homes and if you choose to pursue a rent by the room strategy in can create additional cash flow.

What he meant was, he already knew it was a great deal and advised me not to get caught up with over analysis and miss out out on the opportunity.

Or can you still run everything through your personal return (just want to make sure that I can deduct things such as HOA fees which I can do if it is a rental).2) If I do decide to run everything thru my personal tax return (save on LLC fees), should I at the least set up a separate bank account to track costs separately?

From a legal standpoint, many investors set up an LLC in the state where the property is located (Oregon in this case) to limit liability.

R 10 and R 15 are scooped up by developers quickly .

Their businesses have a lot of names, hard to keep up.

It didn't sell at auction, so not sure what they ended up doing with it....maybe tried again later or put it up OTC. 

Op ex ratio may end up being more like 45% or perhaps 40% with newer high quality construction.

Urban Lot Splits (ULS) allow you to divide a lot into 2 parcels, and Multi-Dwelling Unit Developments (MDUD) are allowed up to 2 units per lot.