Make me an offer, I'm thinking Arsenal/United 1 & 2 
How about United not winning a trophy and not finishing in top 2 then? To me it seems way more fair than H2H with Liverpool.
Alternatively you can take any of the following:
LFC higher league placement than United
City higher league placement than United
Up to 10mBTC, I'll let you pick the amount.
how about Pedro vs. Ekitike goals only? (I don't even know who our main striker is right now.) If you sign Isak, we will cancel the bet.
Sure, you're on. I pick Joao Pedro.