Wireless Joint

I currently have an Amazboost signal booster that only supports boosting 5 bands of cell phone signal. I'm thinking of getting a second booster from Bamwirz that's a bit stronger, and supports 8 bands.

My question is - would it be possible to put them on opposite sides of the house, connect the two boosters into a single line with a 2-way coaxial cable splitter, and then run that into a single booster in the house?

Nope! You will cause all sorts of issues.

You're thinking of a multiplexer, and they aren't cheap, and generally only are for use with a single system and multiple antennas. There are more complex ways yo go about it, but I'm guessing you don't have an industrial sized budget.

Is this for phone voice use, or data use? Both is fine, but these open air repeating boosters are really optimized for voice networks. The M2M versions are better suited for direct to data device use.