<prompt> Human: Im purchasing a home Yay!. Really great deal! The total cost of the house is 116,000, Im putting down 20 on the house which leaves me borrowing roughly 92,800. The interest rate is 3.5, which seems very low to me. Ive calculated the closing costs and appraisal costs etc. The bank says I will end up paying them roughly 119.414. Ive used loan calculators online and it says Ill end up paying them around 140k, are they lying and trying to fuck me over? It is a 15 year loan.Now here is my question If you did 119,414-92,800 that equals 27,914. Now if I theoretically paid of the mortgage in 7.5 years, doesnt that mean the bank would only make 27,9142? So they total I would pay is 106,757. I will not be penalized for paying more early. Ive already checked on that. Sorry if this seems like a dumb question but Im curious because it looks like I may be living with 4 of my cousins and could in theory charge a reasonable amount of rent to everyone and make double payments monthly assuming they live with me for 7.5 years. Id appreciate not being told how they might not and I should account for that because I know but Im just thinking out loud here. If you need any more information please let me know!  <response>: Now if I theoretically paid of the mortgage in 7.5 years, doesnt that mean the bank would only make 27,9142?No. Loans are very interest heavy in the first years of having them. Take a look at a loan amortization calculator and look at how in the beginning, you are paying boat loads of interest, but towards the end of the loan, you are paying very little. It has to do with how much is borrowed. At first, you are borrowing 92,800, but towards the end of the loan, you might only have 10,000 theyre charging interest on.In your specific case, if you paid off the loan in 15 years, then the bank made 17.4k in interest in the first 7.5 years and the rest in the last 7.5 years.As for your first paragraph, you are wrong with the 140k. I get the same 119k the bank got. I think what you did was you used 116k as the loan amount when you calculated your own interest. That about hits your number. 