It sounds like you have a great background for investing as well as assisting other real estate investors in buying suitable real estate. 

I intend to add a closet to the den and make it a 3 bedroom adding value as well as remodel the entire unit.

Vanguard and Blackstone have a lot of interest here as well. 

You can find flat rate listing agents as well for probably $1000 offer buyers agent $2K so they will take the time to show it. 

You must learn to manage the property well.

I’d love to hear any tips or strategies that have worked well for you in real estate marketing, especially with PPC campaigns.For those who’ve done this successfully, are there specific keywords, ad placements, or campaign types that you recommend?

On top of that, I believe you'd be considered a "high earner" - there are limitations there as well.

And yes, the income from renting is still taxable, but ideally you are offsetting a chunk of that with depreciation which is a non-cash expense.You should read Amanda Han and Matt MacFarland's books as well which are available in the BP Bookstore. https://store.biggerpockets.com/products/tax-strategies-book...

I would keep it in a high interest bank account might as well earn as much gain as you can no matter how small it is.However I think some debt pay down would be great not to the point where you are not liquid enough to Jump at another opportunity or can’t make a major repair when it arise.

Well, what would you do with that extra cash flow?