Are you sure boosters will resolve your issues? Do you know its not a network connection issue? If it were,ethernet connected devices would be dropping out at the same time.
Then, be aware that new boosters are now currently only supplied free if you have the Hub4. if so they are worth trying. If not, they will add a £3/mo charge and they aren't. The maths say you would be far better putting those monies towards sourcing your own better quality, wireless equipment with the Hub in modem mode.
-------------------- John --------------------
My services: HD TV on VIP (+ Sky Sports & Movies & BT sport), x3 V6 boxes (1 wired 2 WiFi,) SH2 in modem mode with Airport Extreme Router. On VIVID200, Talk Anytime Phone, x2 Mobile SIM only iPhones.
Sorry to hear about the WiFi issue you're having. @jbrennand is correct in that there will be a subscription charge for the WiFi Boosters for certain packages and you can find more details here . Do give us more information about your connection such as if you're having problems with the wired connection or using the wireless connection when near the Hub so we can take a closer look at your details.