For the phones I use a combination of WiFi access point connection on my Ubiquiti APs in the home, along with a small swarm of strategically placed Bluetooth low-energy beacons around the home. A beacon in the drawer where we keep the wallets, one by the coffee machine where there is a charging cable, one by each nightstand, one in each bathroom, one by the kitchen computer, one on the dining table, one at each desk in the respective home offices, and so forth. I can query the Unifi API to determine which AP the phone is attached to to get a coarse "Justin's phone is attached to the dining room AP." The phones roam from AP to AP correctly so long as you dial down the power on the AP so it only has a 3m or 5m range. Multiple APs in the house let you roam easily and give good signal no matter where you are. I also query the beacons at the phone's location to determine a more precise pinpoint.

For the wallets I use passive RFID tags (sourced from Aliexpress) and a couple of wide and narrow RFID sensor stations, which either run over PoE (only have two of that model) or are powered by a wall wart and connect to the WiFi and they can be easily polled. "Your wallet is in the dining room" gives me the wide range -- around 7m radius in real world conditions -- and multiple wide range RFID sensors can then be queried and the positions triangulated (though not entirely accurately) based on response.

The narrow range RFID sensors are strategically placed and cover about 18" (45cm) radius. That gives me a more granular "your wallet isn't where it is meant to be" report but it does give me "Your wallet is in the 'going out the door, take these items with you' drawer" to make sure the wallets are put back after usage.

For the pets I use a device known as a Loc8tor (British company I think) that is attached to the collars, essentially active RFID (not quite, but that description will do for this discussion), and several custom built sensor location hubs.

For the tracking I took a lot of ideas from supply chain management and retail environment solutions. Many years ago I worked on a "Big Brother" project for a high end shopping mall that could do all sorts of scary tracking of phones long before smart phones were a thing, that fortunately never launched. Now I look back on that, I shudder at the implications. I also worked on a project for the hospitality industry that can accurately track a guest's RFID tag worn on a lanyard or a wrist strap as they move about a facility.

There's a lot of things I would change if I were doing this over again, or spending any kind of time on it beyond a four day weekend. I would also not use active RFID at all and just go fully passive. And I am not even sure I would use BLE beacons for phone tracking, instead perhaps opting for more WiFi APs to cover smaller areas. You can dial down the power to an AP so it would serve the exact same purpose and Unifi make some wall mounted APs that are very nice. That said, it would require a lot more cable runs in the home to do that, that I am not willing to undertake.

If all you want is a heat map, and you have multiple WiFi APs, depending on the brand of access point, you can easily track your phone as it hops from AP to AP. Some of the research in how the WiFi radios of an access point respond to a person being in proximity to them (a few metres) could also be deployed for just simply tracking people.

The WiFi AP roaming and tracking is already a thing built-in to most enterprise devices. The WiFi of the company where you work already knows where you are, with reasonable certainty, and they know precisely how long you spent in the bathroom and pretty much you're reading in there. The only thing I really did different was "Weasley Clock" the phone tracking in to an easily read smart home dashboard.