D160's work ok. As long as you don't drop them. You can put 8 on one base and have repeaters off that. Up to 6 repeaters. They are inexpensive. The phones require essential edition, IP Endpoints, and obviously a VCM resource of some type. Coverage on the D100 base should be about the same as the 3920 base. The D100 is POE, so if you go that route make sure you have POE or a injector.
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