Contract agreement or what kind of deed of sale?

May parents has partially paid a house and lot sa pinsan ko kc nangailangan sila ng pera. Ang property po ay binabayaran pa ng pinsan ko sa Central Bank na naka contact to sell siya doon (bet sa pinsan ko at central bank) may 10 yrs pa ang amortization. Dati kc sa central bank pwede mo pasalo ang property sa iba then all papers will be transfered to the new buyer. Kaso ngayon di na nila pinapayagan yan, maybe kc matrabaho. Ang mangyayari kc, once na fully paid na ang property sa bank, lalabas ang papers sa pangalan ng pinsan ko, then ililipat pa sa pangalan niya ang title from central bank to her. So meaning we will still wait for that time to come since 2 properties etong nakuha niya pero isa lang ang nabenta sa amin. Hindi rin kc pwede bayaran muna ang isa kc daw isang contract to sell nasa central bank.

Ano po kaya ang klase ng agreement ang gagawin namin, kc this december babayaran na namin ang balance tapos kame na ang magtuloy sa amortization, pero ang papers sa central bank nasa pangalan pa nya. Can we execute deed of sale? Or maybe contract agreement po ba? Please help. Para lang po may legal papers po para di po tatakbo pagdating ng panahon since, nasa pangalan pa nya ang papers after full payment.

Maraming salamat po.

(My Tagalog is bad.)
Do you mean the property is COLLATERAL for the bank loan, but the property is NOT REPOSSESED?

If so your cousin can sell the house, BUT the loan need to be solved at the transfer. So you need to talk to the bank (or any other bank or Pag-Ibig) so you get a loan for the part you can't pay direct.
If there are any unpaid property tax, that will need to be solved too. The cousin can SIGN BEFORE that, but you will not get the property registered in your name before that's solved.