Have you reached out to any agents (least effective in my opinion)?

All good points  , I will need to take those into effect. 

What are the best and time effective ways to build credit?

The new loan or refi (not sure if you are getting a line of credit or pulling equity) will ultimately effect your DTI so be mindful of that.

From what I have read, their measures seem to be the most effective.

My recommendation, though not specifically about real estate, but the philosophy definitely applies to real estate is "The Compound Effect" by Darren Hardy.

The effects of a collection a long-reaching in this way, so your best bet is to get this fixed ASAP and you be the one who initiates the contact. 

I dont think there is any minimum, really, but the effect of rehabbing brings up the price so the refi appraisal is where you need it to be. 

@Dan Mann Hey Dan I don't know a whole lot about that but I was looking at a similar plot property in Florida to me that seems really good and especially if you can rent the storefront to somebody who also is renting from you as their business that wouldn't possibly work really well I've seen it done I don't know if there's any legal paperwork you need to go over but I would definitely contact commercial brokers and ask them

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