I understand, in theory, what to do and have been reaching out to do deals, but I still seem to slide into my buy-and-hold real estate investing ways.

@Kyle Crouch, because you already own the land you cannot exchange for any subsequent improvements on that land.You could exchange into a new build where a builder owns a lot and is building a house on it. 

I slightly protect myself by having a sliding scale with the renovation costs. 

This inconsistency raised concerns about the veracity of their operations.Furthermore, during a subsequent call with the group, my client expressed reservations about moving forward based on the discussion and the information presented.

Subsequently they're required to have bond and liability insurance.https://www.procore.com/library/texas-contractors-licenseTDLR licensinghttps://www.tdlr.texas.gov/Desoto building dept.

The water damage stretches from the header above a sliding balcony door all the way down the drywall on both sides of the sliding door and even to the abutting kitchen’s drop ceiling.

It depends on the deal, but what we did was give the PMP (Private Money Partner) 50% equity in the property to fund the entire entry fee.Thats not necessarily a rule of thumb.This to me is a sliding scale based on the Cash on Cash return you can expect.Further , we offered our partner 75% of the cash flow until they are paid back in full, then the cash flow return drops down to 50%.All liabilities would also be split 50% with this partner.We called the company we use , who establishes our LLCs, opened an LLC, wrote up an operating agreement and a JV agreement that outlined all of our responsibilities for the asset.

The point here is, because I thought my bid would only go toward 2007-2008 (and not subsequent years), I calculated my maximum bid way too low.I'd been trying to contact the owners (out of state, inherited the house, in financial difficulty themselves) in vain since September 2014, so I am almost 100% sure that they will not redeem the tax lien, or even know it's been sold. 

Subsequently, we discovered multiple leaks in the roof, resulting in water damage, including mold growth in our closet.

Subsequently, we discovered multiple leaks in the roof, resulting in water damage on the top and bottom floors, including mold growth in our closet on the bottom floor.