I've been looking for a deal on the latest Yale Smart Alarm and this was the cheapest I could find the SR320 version (£290 on Amazon or £259.99 at Costco online but out of stock)
Instore only, but I can find stock in most stores near me to reserve and collect.
This model includes:
1x Smart Hub
2x PIR Motion Detector
1x Door and Window Contact
Fixing pack and batteries
You can arm/disarm and configure the alarm via a smartphone and also add additional accessories. I also bought a 3x pet sensor PIR pack from Amazon for £73 and an additional keypad for £25. You can also add a PIR image camera that camptures images and displays on smartphone.
This model uses the 868MHz frequency that is tightly controlled, meaning a clearer channel with less interference.
No idea how easy it is to set up - that's this weekends job once I've ripped out the existing wired alarm :)