Bought the 3 pack PX50 - Wish I had bought 2 x 2 pack (total 4 PX50)

I need 1 x more in the garage as the mesh wont reach - needs power line

Do I really now need to buy the minimum £200 2 pack?

Whats wrong with selling 1 x PX50

The help-dosk said buy a single P9 but I read on the forum that P9 and PX50 are not compatible?

The power line would then mean I have wifi in the Garage which is away from the house and unreachable on the mesh?

Anyone else had a similar question?

The House has PX50 x 3 with the main unit attached to a BT Halo3 Hub.

Thanks

Stew