Intermittent connectivity in a business setting

any chance you have coax ran through the home? 
or reasonably updated wiring? 

Reason I ask is you could use moca adapters (ethernet over coax) or powerline adapters. 

Stone is amazing at blocking wifi. And the satellites still need a decent signal to connect back to the primary router on. 

If its being blocked, they're going to struggle. But they do support a wired backhaul. that'd be where the moca or powerline adapters could come in. 

Sadly, the older homes with stone/plaster lathe struggle with mesh systems unless they're hardwired in.