@Sol BergrenBP had a legend on their podcast episode 399: Jeff Thorman who discussed this common problem.My experience there's a handful of root causes:- Subfloor is not level - in which case this is bound to happen no matter how well you installed- Improper installation - I've found the planks seem tight when they typically have a small bit they could get tighter which is why I always use a scrap piece of the interlocking flooring, then while installing each piece of flooring, I pull into place manually as best I could, then use the scrap flooring to lock into the open side of the piece I'm installing and tap with a hammer as needed until the pieces is truly secure in place.

No 1 of the individual could replace USD, no, only China and that's a GIANT "if" requiring nothing less than radical change of their entire system of governance and social framework of such that's rooted many many generations long so, all but no chance there alone. 

If something obstructs the sewer line like tree roots, and grey water is trapped in the pipes and overflows the lowest point that could be covered.

And eventually, they also fail financially, because over time capex exceeds cash flow.So I am very much in favor of @Tim Ryan 's idea: pick a market and grow roots.

they get their roots in MLM  just like Amway selling the dream. 

In fact, the residents are deeply rooted - "mobile home residents are less likely to move than residents of site built houses.  

I work for a builder, a lot SF investors laying roots here.

I would recommend investigating the root of the problem first.

My pleasure.To answer this question you first need to understand what a motivated seller is because this is the root of all the inconsistent advice flying around.

Have you ever had a root canal?