New Home Owner - looking for advice

Do you want the ability to play the same source, such as Tidal or the audio from a football game on TV (or another source such as a turntable, CD player, etc.), to all the zones/ rooms? 

Do you want the ability to adjust the master volume as well as trim individual volumes in different zones while playing the same source, as above? 

Do you want the ability to pick and choose which zones/ rooms are selected to play different audio is smaller groups?

The easiest way to skin this cat is Sonos.  It's the best solution that's made for this situation where it's not some cobbled-together mess that's a pain to use by everyone in the home.

There's more to this than just throwing some monoprice speakers in the ceilings and some amazon amps in a closet.

WiiM is good but does not have Airplay.  The systems that offer Airplay include Sonos, Bluesound, HeOS, and MusicCast.  WiiM is significantly less costly to implement.  So ask yourself how important is Airplay?  

I would advise you to consider a multichannel power amplifier…there are many on the used or new market from Niles, Russound, OSD, often with 12 channels, that are configurable, bridgeable, with either class AB or D topology, and get as many WiiM Pro or Pro Plus as you require zones…and patch away.

The main argument for HeOS and MusicCast is if you want to integrate a TV/Surround system into the mix of zones.  Those systems are built into AVRs from Denon/Marantz or Yamaha respectively, and both have solutions to expand into other zones within the platform. Bluesound does the same with NAD.  Of these, I like HeOS best for ease of use, and Bluesound for ultimate best SQ, but MusicCast is by no means far behind.  
Another path is to use Sonos Ports and a “Works With Sonos” AVR…like Sony, Onkyo, or Pioneer.
All of these require a well designed, stable WiFi network as a prerequisite.

I have a Niles multi zone amp(got pretty cheap on ebay), Sonos Connect for audio and a 4 channel audio mixer so i can do Sonos and TV at the same time.  Nothing fancy but been using for 5 years and it always works well.

I would suggest looking into Roon

If you are going to use the existing speakers, you will want to check and see if they are 8 ohm, or if they have 70 or 100 volt transformers on them, which is not uncommon in an installation like this. If so, you will either need to replaced the speakers or not use a conventional stereo amplifier with them.