Happened to me. Was hired as a freelance in a company that had the "no telecommuting" policy. After 1 year and a half there, I got slightly bored and wanted to leave (long-commuting, like 2h, is too long when the job is not that appealing anymore).

As I have been performing above average for all my time there, they insisted to find a compromise so that I wouldn't leave. Told them I would consider staying but with 2 days per week telecommuting, 3 days on-site. I already had their trust, they knew I delivered, so they agreed cheerfully.

Some coworkers who tried to get some telecommuting days before got slightly angry at management for a few days, but not that much, as they liked me staying and understood why management dit it.

I think it worked because I was just not bluffing, and after more than 1 year working there, they fully trusted me. It would have never happened if I had asked for telecommuting at day 1.

Yeah, find out what the company policies are. Those might trump the job posting if they really want you.