I never take anything anyone says verbally as a promise since that just leads to a "your word versus my word" situation. Business is done in writing, at least through email, these days.
Telecommunications is not cheap. And we're not living through a time when we can rely on laws and regulations to make sure it is cheap for us if we cannot afford it to be expensive. There are approaches you can use to get a slightly better deal, a few times, but after a few times getting such accommodations, you really truly have to be willing to live without what they're offering, walk away from them for a while, in order to do much better than the advertised price. As much as we consumers are learning the game from our side, service providers are learning the game from their side as well.
High-speed broadband Internet service, specifically, is an insidious situation in most areas. With television, you can surely live with out it (perhaps, these days, even more so than Internet service), and there is effective competition for television service in practically every jurisdiction in the nation. Ditch Charter or Time Warner, and most landowners are still able get television service from DirecTV or Dish Network, and the law also secures that option for many renters (though it would be great if the political environment was such that renters were granted the same rights as landowners - we're not living in the 19th century anymore!) Furthermore, as long as you have high-speed broadband service, you can get a decent level of television service, now, that way. You have choices. You have some control.
With high-speed broadband Internet, many areas have only one viable supplier. That's because, according to the law, Internet is Internet. And surely everyone has many sources for Internet service available to them. The problem is that the law doesn't distinguish between dial-up service and broadband, and surely doesn't differentiate between levels of service that effectively support services such as streaming video from those that don't. And in today's political environment, it isn't likely that that is going to change. Things are arrayed in the service providers' favor, and that's the way we've collectively decided to have things, now, even though we hate it when it adversely affects us, personally.
To be fair, while part of the problem is that the law isn't on our side, another big part of the problem is that we don't acknowledge just how much the service is actually worth. The critics cherry-pick statistics when comparing the US to other nations, but the reality is that we actually have available to us the best Internet service available, an amazing accomplishment given how many Americans live remote from city centers compared to other nations that seem to have better service. The service many of us enjoy is the absolute Cadillac of Internet service. Even if we don't acknowledge all the value offered, the cost is warranted. And anyone who owns stock in Comcast or Time Warner can see the reality of that: These aren't super-fantastic stocks that yield many times the gains of other stocks. They're just "okay" holdings.
The fact that our Internet service is the Cadillac of Internet service leads to another obstacle for us - one of perception: We have luxury service, in the US, and we have chosen to treat Internet service, in general, legally like a luxury, and so it is going to be priced like a luxury. As I mentioned above, the law doesn't differentiate between this Cadillac of Internet service and dial-up service. However, despite that, consumers don't have an appreciation for sustenance Internet at a lower price. You could get Internet for $30 a month and be done with it. You cannot stream video, perhaps, but you would have Internet access. It's simply not appreciated by consumers in the way that our laws are structured to presume it would be.