For businesses:
https://www.ringcentral.com/office/plansandpricing.html#

Dialpad.com
Configure VVX450 Phone for Dialpad: Install Obihai firmware from https://support.google.com/a/answer/9311828?hl=en (put in link to XML file in config, phone will then prompt to update using it).
Then set up provisioning server using:
https://help.dialpad.com/hc/en-us/articles/10967111627675

For Resellers:
https://www.whitelabelcomm.com/atlas/


For personal use:
https://www.obitalk.com/obinet/ (Free service with Google Voice, or other service)
http://www.anveo.com/anveoforobitalk.asp - If you have an Obihai then you can use their cheap service plan
http://www.anveo.com/enter.asp - Setup VOIP service. Cheap, customizable, works great.


PBX:
https://www.freepbx.org/get-started/


Phone Hardware:
OBi2182 WiFi VOIP Phone with Power Adapter - 12-Line Cloud-Managed Gigabit Google Voice Phone with Color Display
https://www.amazon.com/gp/product/B076JKV5CL/
Firmware update 5.2.3-5330 July 2021: http://www.obitalk.com/forum/index.php?topic=9.0
Manual: https://www.obitalk.com/info/documents/admin_guide/OBiPhoneAdminGuide.pdf

Refurbished phones:
https://www.tritondatacomonline.com/pages/search-results-page?collection=phones-polycom

Phone issues:
https://www.fixya.com/support/t13186578-panasonic_kx_t7425_phones_stopped


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