My wife and need a hotel room for one night near Charmartin Station in Madrid. We would be grateful for any suggestions
Sounds like you want to be there for easily getting on a train. Which train? Maybe there's somewhere else that would be nearly as convenient while being a more preferred area?
Actually you could stay about anywhere in central to north Madrid and be within easy and quick taxi range. That is a small train station. Actually you should probably move your question to the Q and A section for Spain. That is more appropriate than posting it in the Trip Review sections that goes get as much traffic as the Q&A. You might send a couple of minutes understanding the structure of this site so you get better answers to future questions.
There is an hotel literally over the station, in the same building. I was sent there for business a few years ago for a couple of night. It was fairly run down, noisy groups, paper-thin walls, smelly room, mediocre breakfast (the worst I ate on Spanish soil). I read that now it has changed name and was renovated, but I do not really know.
But I remember the new cercanias (suburban trains) line to Atocha as a breeze: we could get to Puerta del Sol in less than fifteen minutes - on huge suburban trains, not the tiny trains of the Madrid underground. It could work the other way round: if you manage to get a room near one of the cercanias stations you can get very quickly to Chamartin.