I won't say that the extender wouldn't help, but man those things have been a source of some serious fussing lately on the forums with connection issues and such.  All I can say is to keep on it with Vzw about getting one to try.  I can only speak from experience there.  Also, I can speak to the "Was great, now it isn't great" signal issue.  Technology changes, geography and industry changes. New subdivisions and buildings go up and people move in with all sorts of stuff that may or may not interfere with a signal.  Unfortunately, the agreement gives Verizon an out when you sign it stating you understand they don't guarantee signal strength of any amount anywhere, especially inside buildings of any kind.  They tell me that their only obligation is to provide calls, texts and data while on their network, wherever that network might be found and successfully be connected to.