Windows 7 Laptop wont connect to Hub 5

A wireless repeater would not need to be on the same electrical circuit. You use it in between the VM hub and the device location. It relays the wireless signal received from the hub to give greater coverage. It may (possibly) give greater compatibility with older devices than the Hub 5 does.

The Hub 5 uses wireless AX standard but (the last time I saw any screenshots of the Hub 5 interface) there were no means to turn off the AX standard and use older standards only. This causes problems for older devices as mentioned above.

If you have had problems with a Hub 3 too, and on other devices and are getting network log errors, then you may have a connection problem and none of the above may be relevant to your actual problem or the two problems may be interlinked.

You seem to be describing two (different?) problems: a wireless connectivity issue in your home/connectivity for an older device plus a problem with your broadband dropping out.

Are you tracking you connection with a BQM?

https://www.thinkbroadband.com/broadband/monitoring/quality

If you post up your hub stat's (downstream, upstream, network logs) someone on here may offer to check them for you.