How to make a confident offer?

[John Spina jr]

Aside from calculating the NOI, ROI, cash on cash return, and the comps. If someone needs to finance the conventional way, do they need to sit down with a broker and see what kind of payment they'll be making and at what interest on every property?

  How else would someone know exactly what the expenses will be for each property? (Mortgage payments, tax, insurance etc.)