Most cost effective way to solve cell coverage inside your building
The more buildings are insulated with sound proofing, low e glass, etc., the more cell coverage is negatively impacted. Most of the options are effective but more expensive than anything that can reasonably be justified (2-5$ sq ft) and other solutions are almost strictly residential. 

Great commercial repeater systems exist which can be had for about .35-45/cents per square foot. They immediately boost coverage and take only about a week to install. 


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