We are also getting a forgiving loan of 30k for the duration of 10 years from the county for 1 unit if we rent out the 1-bed basement unit to a household with income less than 100k and at the rate defined by the city )(~1183+ utilities) for a 1 bed unit.

Now the HOA asks me to apply a padding/underlayment under the floor, but the floor I purchased already comes with a pre-attached underlyament....Now I am not sure how to handle this issue, I just bought some area rugs to reduce the noise for now...

Once you have that rolling and you understand the game you can then invest your W2 income into additional properties. 

For me it's worth it, because REI is just one avenue of my family's income.

They want to buy the home from me but are running into issues with debt to income ratio, so not eligible for FHA. 

Thanks to the Cost Segregation Study, the property investors accelerated the depreciation that the first year depreciation was approximately $1,629,844.Through the cost segregation study, they were able to reclassify approximately $2M to a 5 year useful life, $2.35M to a 15 year useful life.The use of the accelerated depreciation strategy helps real estate investors to reduce the tax liability immediately which therefore increases their bottom line due to the offsetting of income.

I had a remediation contractor come out, and he told me the levels on the report is what he'd expect from a basement in Portland, and any amount of washing / bleaching wouldn't reduce the levels much long term as more moisture would enter the space up from the slab because concrete will always give off some moisture, and he couldn't really recommend much remediation. 

Currently, I find myself in the 37% tax bracket due to W2 income and I'm eager to explore avenues to shelter taxes through real estate investments.

Will this area see a huge increase in value and rental income?

On the equity side by increasing net income and or decreasing risk, on the debt side by “working” the note.