remote monitoring of business partner

I have a very good business partner who lives in a town about 100 miles away from me. Just recently I been getting some odd demands for cash payments. I think the problem is my partner making some deals over the internet and not telling me...so my question is how to monitor there computer. I would rather have some evidence before accusing them of anything...any ideas

 

or better still finding there password for the email, just had a demand of final payment on 10,000 dollers of camping equipment...when we deal with holidays in hotels...

 

you may (both) just be getting scammed because you have a travel biz.
if scammers send letters of demand to enough businesses like yours and get one to actually pay, then they are laughing.

So consider that this may just be an email scam and not your partner being dishonest.