I have a problem.

I have a 16mths old who i'm listening to at night on baby monitor. I went through 2 Tomy Walkabout Premier monitors, the first one was from my first child, which worked reasonably well the first year, so I got a second one, the exact same model, and then everything seemed to be breaking down. OK, long story short, both broke down on me now.

1, I think I still want a monitor, our room is quite far from my boy's room, and I do want to hear him first thing when he cries at night. Sometimes, I'd like helper to take the night shift, and she is a very very sound sleeper, I don't think she'll wake up if I don't have a monitor blasting in her room.
2, I figure I only have max another year to go to use a monitor, so I don't want to get something too high end and expensive...

Questions:
1, Any recommendations on what brand I should get?
2, Anyone ready to part with theirs in good working condition? I don't mind going second hand on this one. I'm looking for something that is quiet and will not have static sound, as we use it mostly at night.

thanks,
alfreda