Multi zone amps

Looking to set up a multizone (kitchen and living room) system at home. Am looking to use B&W LM1 speakers (2 speakers/room) on wall mounts and a HSU VTF-1 sub in the living room. Doesn't have to play different inputs in each room, but is important that I can play through A and B speakers at the same time. I know that Denon Amps (and probably a number of others for that matter) can do this, but wondering whether there is a better option for quality out there. Digital inputs aren't critical (could buy a DAC).

Any recommendations for an amp (new or used) at around the $500 mark, that could meet this need, would be much appreciated.

Are you looking for an integrated amp or do you already have a preamp?

I noticed that the LM1 is rated at 8 ohms but I'm puzzled by the "(minimum 3 ohms)" phrase in the spec sheet. If these speakers occasionally dip down to 3 ohms, that will be a problem for most integrated amps when both sets of speakers are playing.

If you already have a preamp, then perhaps something like a NAD CI 9060 or Rotel RMB-1506 should work fine. I don't know what the used prices are, but perhaps you could find them in your budget.
I have a Denon multi-room and it makes things simple. However, an external amp will get you better sound. The Denon multi-zones are mid fi sound at best. You can use a Denon 385? with a nice power amp for one of the zones.
I've got a couple of restaurants and I've used a few. Right now I am trying a few AMC's, seems to work fairly well. My favorite system right now uses two rotel RMB985's I think that's what they are- running five zones-all ten channels used with B&W 303's. Rotel and B&W seem to like each other and work well together.
Thanks for all the feedback.

I have a pre-amp that I like a lot (Bryston B60). Could I use this to drive a multi-channel power amp that would in turn drive a second/third "zone"?