Can you have two Sky Broadband boxes on one property?

[CookieHouse]

Basically, I have one Sky box near the front right of my property. It reaches most of the house perfectly, but I have an office now set-up in the garage, which is the same side of the property, but further away, with about 3/4 walls separating it from the box. It's also outside the property, and so it doesn't reach the garage at all. I expected this.

I'm quering to see whether to see if an additional Sky box on the same package/ an extender/ booster that can replicate the same speeds we meet in the house, in the garage, or whether to install a LAN cable from my box inside the house, over to the garage. This would be about 16/18 feet away. 

Looking to do this promptly. If there is a way to get the wifi box/ one installed to the garage, can someone explain the process exactly for me. 

Thank you for any responses 

[TimmyBGood · Accepted solution]

@CookieHouse 

Ethernet cable is always preferable.  Sky won't help with supply or installation of that or any other method of reaching an external building though: such locations are specifically excluded from the various 'guarantees'.

[Osmond]

Running an Ethernet cable from the front of your property to the outbuilding will give you the fastest and most reliable connection. What I did was place a small gigabit switch next to the hub at the front, then ran a network cable along the outside of the house to the back, where it connects to another switch inside the outbuilding.