Bellies in Plumbing- Is It Worth the Fix?

[Adriana Escalante]

Hi BP Community-

I've been lurking in forums for a while but this is my first official posting!

I'm super new to Real Estate and purchased my first home in Austin, TX last June. This house is my primary residence but I have slowly been renovating the space and hope to start "househacking" in the next month. We've been nearing the finish line renovation wise and just as I was starting to get excited, disaster struck. 

We noticed some light leaking in our guest bathroom around the toilet over the course of the past few months but we didn't originally think too much of it since we planned on renovating that room. We replaced the toilet including the wax ring and thought we'd solved the problem.

Fast forward to two days ago, my partner and I took two showers back to back- about 30 minutes of water use from the master bedroom(not the leaking bathroom). When we passed by the guest bathroom, it looked like someone had poured water on the floor and it seemed to be seeping from the bottom of the toilet(awful luck considering we just renovated that room, replacing tile, and drywall etc.). 

Since we still have our home warranty, I had a plumber come out because I assumed we had some sort of blockage. The plumber used his snake camera, could not find a significant blockage but told me that he did see "bellies" which would be around a $20K repair and would consist of extensive plumbing work around the house. Of course- this didn't sit well. 

So, I come to you, BP Community, with a few questions:

1) Has anyone encountered issues with bellies in their plumbing? If so, what was the actual cost of repair? From the plumber's suggestion, it sounded like he thought the best course of action would be to replace ALL plumbing but that seems like overkill to me. Is there a way to narrow down the possible offending pipes without costing hundreds of dollars?

2) Is this sort of repair worth it? My fear is that increasing the water usage by adding additional house guests(house-hacking), we'll continue to see an issue. We also planned on Airbnbing the house when we leave town and have room for 10 guests. 

3) If we were to flip this house(another option we've considered), what sorts of disclosures need to be made about this plumbing issue? The plumber who came out recommended flushing the system a couple times a year and we shouldn't have a huge issue but there's only two of us living here currently. 

Thank you in advance for any answers provided- We truly appreciate any and all help!