Beacon purchase choice

I need a piece of advice on the beacon purchase.
I’m a student starting to work on my bachelor.
An idea is to make a mobile AR app that would pinpoint the location of devices to a matter of a few tens of centimeters
You would stick a beacon in the form of a sticker or a keychain to some of your belongings that you wouldn’t like to lose (but maybe lose on a daily basis like keys or phone or anything else).
When you want to find some of those beacons, you would open the app and choose the thing you’re trying to find and the app would direct you to the item.
What are the best beacons to buy for this kind of use-case?
When answering, consider that this is meant for apartments (or houses) that have several rooms and you have to find the device in any of the rooms.