I wouldnt suspect a public safety agency to rent air time on a commercial 900mhz system either
Possibly a security company or ambulette type services or maybe a very small township but thats about it
To each their own however
Why i estimated PDV was due to the fact they have many towers across many states and have possibly the largest 900mhz system in the nation at the moment - but it could be a separate radio company
Whats happening recently is Sprint is auctioning off the former Nextel frequencies so radio companies would definitely want to get their hands on some 900mhz freqs
Just like for a while they would do LTR or Motorola systems - looking to the future they will most likely be digital DMR or Nexedge systems
In my area (NY/NJ tri state) there is even a electric utility who is building out a 900mhz P25 system