Currently using a PRI. We have a block of 100 DIDs for office phones, but wouldn't mind buying 200 more for hotel rooms if that's what is needed.
Running 8.0 SP3 PR1. Active Software Load 14.0.3.22.
This is exactly what you need to do, and then setup CESID for each room with a unique ID, and then have your carrier submit the necessary information to the 911 database (or coordinate with your local E911 coordinator, varies by location).
I am not entirely familiar with Kari's 911 law and how it applies to your specific situation and at what granularity. I would suggest contacting your local E911 Coordinator and working out the details.
My point is, other than needing more numbers, you have everything you need to be compliant all the way down to each device.