For the right amount of money, that professional installer will make the journey to your house to cable and set it all up. An electrician may be able to pull cable for you, just make sure they do know how low voltage stuff works. Some electricians do...some don't. I had one who wanted to snip a cable and tee in another run not understanding it didn't work that way.
My house quite a bit smaller, and there is no way a single device could possibly cover all corners of the house properly.
#1 - I don't want a funky looking device sitting in the middle of my living room since it is the most central part of the house
#2 - I don't want just single client performance, I want to make sure 5 or 6 devices could be doing 50Mbps streams concurrently
With that in mind, if you really want to take advantage of 1Gbps Internet...which pretty much very few people "really" need...you will want multiple wired APs providing service across the property. I have 1Gbps Internet as well and rarely ever do we use more than 50Mbps at a time unless I am downloading an ISO image. But for $20 more a month, why not have 1Gbps instead of 100Mbps?
What you need to decide is where will your wireless clients be located and make sure you have an AP nearby with no more than 1 or 2 walls/floors between. The less obstacles, the better performance will usually be. Keep in mind as you add more APs, the complexity of tuning power levels comes into play to try to get your clients to roam properly between APs.
You say hitting 200-300Mbps on a wireless device? That sounds pretty good to me. I'm sure your Mac can hit higher with the right gear, but most of your other devices are probably 1x1 or 2x2 devices and are unlikely to go much faster.
I can hit just shy of 400Mbps while sitting in my living room using my HP laptop with 2x2 AC. If I need faster than that for large file transfers, I walk to the basement and plug in a cable. I can usually get a minimum of 200Mbps just about anywhere inside of my house with my laptop. My phones are usually closer to 100-150Mbps which is way more than a phone will ever need. I know for sure we can handle 3-4 Netflix streams at a time as well as file transfers from the laptop without any issues at all since the clients are distributed across 3 APs. No matter what my wife or guests are doing upstairs, they have zero impact to what my WiFi performance is down in my office since I have a dedicated AP.
So your original question:
1) What cable modem would you buy?
- have no advice here...I'm on Fiber so no modem
2) What wireless routers would you go with and how would you connect them?
- wouldn't use a wireless router, would go with a dedicated router and dedicated AP
Router - If not doing anything fancy, just use the ISP router and disable the WiFi
Router - Otherwise....well...yeah, not sure since I don't know what devices can handle 1Gbps
Router - I run an x86 box running SophosXG for more advanced features (previously ran pfSense)
AP - UniFi, Cisco, and several others have decent priced options available
AP - look for 3x3 capable AC devices if you want to improve your speeds on your Mac
AP - otherwise 2x2 capable AC devices are probably good enough for the rest of the house
3) Would you use a switch or two ?
- this all depends on where you have network drops and the distances on them
- hard wire as much as you can
- decide if you need PoE to power APs