OP, you should give some more details about the layout of the property.
A lot depends on the materials used in the property. I have seen old houses where a router can easily reach all rooms across 3 floors, and modern flats where the very same router struggles to get the signal to the other room.
What is your budget? How much are you willing to spend on this?
Wired is always best. If you can run ethernet cables from one room or one floor to another, and then set up a separate access point or router in the other room/floor, do that, the connection will always be better than what you would achieve wireless. The Unifi AC or AC Pro are amazing pieces of kit, miles ahead of any network-supplied stuff, and they also look OK (google them, they're like a whitish dish), but they are only access points, not routers. If you don't know what it means, then configuring them won't be for you
If you can't or don't want to run cables all over the house, you must make sure the repeaters you use have 2, or preferably 3 channels, so they use 1 to communicate between them and the other(s) to send data to you. Otherwise speed will be slowed down too much. This is a good one:
https://www.tp-link.com/uk/home-network ... der/re365/
Depending on your needs and the layout of the house, you could also think of a mesh wifi system - they are basically a set of repeaters like the TP Link in the link above.