I would advise you to avoid any deal which involves pledging your parents' home as security to cover your training costs, unless you are certain that you will be able to pay back the loan whether or not you succeed in aviation - unless you want to be responsible for your parents losing their home.
Think about it, please!
Incidentally, I find it somewhat incredible that some parents will actually acquiesce to such an arrangement. I certainly never would for my children. I suppose sometimes love is more than just blind...
Scroggs