When does real estate property ownership vest or transferred?

When does real estate property ownership vest or transferred? Such as in a situation that you have a contract and the provisions of the contract provides for the installment basis payment. Let's say you bought a property and the payment is over five years. If you sell the property to the other person in an installment basis, can you already mortgage the property or can you sell it even if it's under installment. What are the laws when it comes to vesting the ownership of the property between to you and to the other person (as buyer)?
Answer

It's important to know the distinction between what is a Contract of Sale and Contract to Sell.

When we talk about Contact to Sell, it means that the ownership will only vest from the full payment. But when we talk about Contact of Sale, it presumes that the property has been fully paid.

Even a particular contract has been designated whether it's a contact of sale or contact to sell, if there's actually no reservation as to the ownership, that would be considered Absolute Sale.

In other words, if the contract does not state that the ownership will only transfer upon full payment and as soon as you sign a contract of sale, ownership is transferred when you moved into the house or occupied the land and start building there. The house or the land is yours even if you're not yet fully paid if you sign the contract of sale. So, what the seller can do if you don't fully pay is not to take the property away from you but to file a case against you for complete payment. - https://www.affordablecebu.com/