With 15 years mortgage you would pay less in interest but pay more in monthly mortgage. If you are tight in money and likely won't have any significant savings in next few years I suggest signing for 30 years mortgage. The interest rate is little high but your monthly mortgage is much more less. In case your financial status improves in next few years you can always make more payments than monthly due and reduce total interest paid considerably. Paying little more money at beginning is much secure than go default on larger due with 15% mortgage.