@James Hamling , I appreciate the straightforward feedback here. To your point of the seller's defense, I think you are spot on. Yes, I conducted my due diligence with professionals and no, these issues were not discovered during that process. If the professionals couldn't find it, I understand it is difficult to prove that the seller would've known about it. Here is what I can prove:
-During the seller's renovation, duct tape was applied over the deteriorated leaky pipes under the crawl space. I know that there was a deliberate attempt to conceal the issue and possibly delay a burst. This is well documented. Sure, the contractor could have done it and never told the seller.
-New drywall was put up directly covering visibly broken and deteriorated stack. This is well documented. I know that there was a deliberate attempt to conceal an issue. Sure, the contractor could have acted independently and did not tell the seller.
-I know that a brand new kitchen was installed, directly accessing and connecting to this broken stack and drain system. It's not whether or not somebody knew that this was wrong; it's WHO knew this was wrong, and how can I prove it. This is well documented. Sure, the contractor could have acted independently and did not tell the seller.
-The seller knowingly provided inaccurate information in our closing documents. He signed every document under a fake address. During the inspection period, I learned recently he shared incomplete/inaccurate documentation for contractors' work on the property, after I requested scope of work, permit documentation, and warranty info.
Obviously, none of this suggests that I have a winnable case, for all reasons mentioned in your's and other's posts. It does mean, in my opinion, that there is strong reason to believe that issues were not only known by the seller but actively concealed through the renovation process, and there may or may not be a way to prove it. That doesn't mean I can or will, rather, it's worth exploring.
I appreciate your level-set, and I certainly have a lot to learn. I am not, however, naive to the fact that sh*t happens in this space. I expected that this would be a messy, difficult, and unpredictable excursion. That expectation reflects my aggressive research, self-education, mentorship, and preparation over the last few years. This was no easy process, and certainly no daydream. It is wildly difficult for a new, young, and self-employed aspiring investor to purchase a viable property in this market, in this highly affluent area, at this day and age. And thankfully I was extremely careful with my numbers to leave plenty of cushion for myself, plenty of money set aside for repairs, and plenty of expectations that things WOULD go wrong. For others, this surely would have been a nail in the coffin.
A quick note - I did get a home warranty at purchase. I also went all-out for insurance. Neither of these cover pre-existing conditions and, regardless, most policies do not cover anything in the first 30-60 days of ownership.
To the entire Bigger Pockets community here, I am overwhelmed and grateful for all the responses, insights, and support.
Don't ignore the crawl space. Don't let the inspector miss anything. Check everything myself. Be more thorough moving forward. Document document document. Get more info from the seller earlier in the process. Double check and verify info. Be careful with flips. Be VERY careful with flips. **** will happen. :)