I just bought this whole-home 3-pack.  Inside it flies.  I have a seperate office in my backyard (approximately 150 feet from the modem).  I put 1 of the 2 nodes in the office.  Sometimes it runs fine (> 200 u/l, similar d/l).  Occassionally it really goes down (50/<50 mbps).  I thought of adding 1 single node in our garage which is 1/2 way between the office and the room with the modem.  However, I can't seem to buy one node.  Is it availabe to buy one and if so where/how?  If not would add another 3 pack help or hurt connection speed and continuity.  Or would the outdoor node you have be a better option?  If so what outdoor unit would you buy to go with this gear?  Thank you!