I figured the only holding costs will be the utilities. 

This strategy requires knowledge of local markets, renovation costs, and the ability to manage or oversee renovations.I am a loan officer and I could advise you on how to tap into that equity and put that money to work.

This will be used for repair cost and down paymentAny advices going forward?

Managers cost so much and make repairs cost even more, I do not see their value until you have 50+ units and no time. 

Can't recommend @Joseph Cornwell enough, he helped me buy my first duplex in Cincinnati and he has a contracting business, so he can give you advice on repairs, remodel costs, etc

renter sucked...didnt pay.... cost me a lot of money blah blah blah.

Consult with a Financial Advisor: Seek advice to navigate negotiations and explore refinancing options that best fit your needs.By taking these steps, you can work towards lowering your interest costs while keeping your loan terms unchanged.

Just turn it off before it renews and that's all it costs you.2.

Personally 0- but I have been through quite a few low cost renter trashed units for sale.

I am looking to see if anyone has any suggestions on how to get an accurate number on rehab costs.