If a sales org is trying to create a deal and they are getting a "no deal templates are available at the deal's project address error," then changes will need to be made in the installers/EPC V2 instance (with Installer admin authorization).
In the installer's instance, navigate to Settings > Installer > Authorized Dealer and find the sales org in the list. Select which deal templates the sales org should have access to.
This should match the list of enabled deal types in V1, which can be found by navigating to EPC > Sales orgs and then clicking into the individual sales org settings.
If the Sales orgs Templates have been enabled and they are still receiving the error, check the installer markets in V2.
V2 Settings>Installer>Installer Markets
Search the zip code. If No items are found, reps will need to reach out to the installer to request the zip code be added to the installers markets.