What to do when the istakhara for marriage is partially good and partially not good. Mufti says it means that the guy is good but you will have to be very careful in this marriage. 
I will advise you to base your decision on concrete things rather than istekhara. Look around in your community and you'll find plenty of problematic marriages that initially had perfect istekhara, also the other way around. As far as I know that is also the majority consensus of scholars about istekhara. If you do not have concrete things to base your decision upon then istekhara won't make up for it.
That sounds like a very political answer lol.
I think Istakhara is a good way to go but now since you are done with it and the answer is not clear, trust your own gut feeling and pray that may ALLAH make that the best for you.
Good luck!
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