Sean, your parents would be taking one hell of a risk, $70,000 is about £37,000, a secured loan for that amount would be about £500 per month with repayments starting straight away, that monthly figure is for the loan taken over 10 years and you would be repaying about £55,000, if your away training for 18 months then your parents would have to cover those repayments for the whole time you are away and until such time as you gain employment.