Dumb question, sorry in advance

[Ron B.]

Sorry in advance, I'm not an accountant and I'm trying to figure out if a property is worth buying by doing my own rough math before paying my accountant to do it for me. 

So I have a $3.5m purchase and have a 100% loan at 7% interest for 30 years.... My question is, do I take the entire 3.5m and add 7% on it every year making the monthly payments $30,138? Or is the 7% over the life of the loan (30 yrs) making the monthly payments $10,402?

Also how does a balloon payment work, say I do 100% 30 year loan at 7% and have a balloon payment in the 5th year of owning it?

Thanks in advance!