We help our clients overcome obstacles, but rely on them to let us know they need some additional help.

I have heard of some investors adding the rehab amount to the HUD to overcome this.  

Something I have to overcome! 

I live in the San Francisco Bay Area and although I have rentals here in the Bay Area my next purchase will be in the Midwest .... most likely in the next couple of months.Through much Persistence I've been able to find agents and property managers in 2 markets that  considering and will be flying to both places next month before making a decision on which one.I used to be completely adverse to investing out of state because I wanted to be able to drive to my rentals and be able to "check in on them" with my own eyes.....until I started listening to the podcasts of people on bp here and how they did it as well as why (cheaper to buy and better cash flow).

If so, how did you overcome it?

Unfair (and unfounded) accusations can be difficult to overcome.  

So I don't know how the slab would adversely affect anything.

The contestability period is just as difficult to overcome for title insurance (and therefore mortgages, etc.) as the redemption period; effectively properties sold at a Texas tax auction will need to mature for two years before title insurance can be obtained.Struck-off properties may be closer to or even past the redemption and contestability periods and may sometimes be available at less than the original minimum bid amount. 

I had always wanted to flip houses, since I was in my 20's, but was overcome by Life (a good and productive one, just not very efficient economically).  

It sounds like you had a lot to overcome.