In fact, they'll likely ask for documentation of any accounts that hold monetary assets. This is because mortgage lenders want to know that you'll be able to afford your down payment – if one is required – and make your monthly mortgage payments.
Installment loans can be unsecured or secured by personal property and other forms of collateral. These loans are considered installment credit, which you borrow in one lump sum, versus revolving credit (e.g., credit cards), which you can reuse over time.
While not required by law, having the promissory note notarized can provide additional legal protection and evidentiary weight in court should any dispute arise over its enforcement.
A contract, under Philippine law, becomes binding as soon as there is mutual consent between the parties, consideration (payment or exchange of services), and a lawful object (subject matter of the agreement). These elements are enough to form a valid and enforceable contract, even without notarization.