Yagi has its advantages. It also has its limits. The Yagi usually helps one of two frequency bands while hurting others. It might help 1x and 3g while hurting 4g. Or vice versa depending on design.
It will not hurt to call Weboost. Weboost was Wilson Electronics before the name change. They will prob ask for true signal level, not cellphone bars on your screen.
I helped a friend install a home base Wilson Electronics booster. We installed the internal antenna in the living room. Then placed his Mifi in front of the internal antenna. Thus gave the Mifi maximum signal. Connected the laptop thru wifi to the 4g Mifi. Strong data with great cell signal for calls in the living room.