Questions about cost of loan (15 vs 30 years)

[Amosse Yovenn]

Dear Bigger Pocket community,

First of all all my apologies if this post seems to have already been talked multiple time - I just have not seen it through the eye of the cost of the loan.

I am considering buying two properties worth together 226.5K USD. I come up with 90.6K and the rest 135.9K is through a either 15 or 30 years 4.5%/year loan.

My question revolves around the "cost" of the loan, specifically if I want to resell the property before the end of the loan. The calculation below includes both the sum of all monthly payment of the load+the capital due at the time of sale. 

- If the resell is within 5 years, the difference in cost between a 30 year old loan and 15 year old loan is minimal. I would pay less than 3K in total for a 30 year old loan vs a 15 year old loan if I sell within 5 years and reimburse my loan. 

- If I resell within 10 years, the difference in cost is 11K

- If I resell at 15 years, the difference in cost is 26K

So my question are:

- For a long term purchase, am I understanding correctly that it would be better to get a 15 year loan? As the 26K would make a sizeable difference vs the additional cash flow you would get monthly by getting a 30 year loan. 

- What index are you using to see if the additional cash flow would be better vs the cost of the loan? For example, for 10K difference over 10 years, would you say that it would be better to have a 30 or a 15 year loan 

- Since most of the loan I can get is ARM fixed until 5-7 years, would you say that having a long term loan and keeping a property long term is more risky since the interest rates will change?

Thank you for your lights on this!

Yovenn