Buyer guides
OFW buyers
You can start a purchase while you are abroad. The dangerous part is authorizing the wrong person, or sending the reservation to the wrong account.
Who should be the buyer
The name on the contract should be the person who will own the property. If a spouse or a parent will sign in the Philippines, they need a special power of attorney that the developer and, later, the Registry of Deeds will accept. A chat message is not that document.
Papers from abroad
A special power of attorney signed overseas generally has to be notarized and then apostilled, or consularized at a Philippine embassy or consulate, depending on the country you are in. Ask the developer which form they actually use before you take a day off work to queue.
Pag-IBIG from overseas
Many OFWs use a Pag-IBIG housing loan for the balance and pay the equity themselves. Membership and contributions have to be in good order. The loan is not approved because a website calculator produced a monthly number. Read the Pag-IBIG guide, then confirm the current matrix with Pag-IBIG.
How to pay
Pay the developer named in the reservation agreement, into the account printed on their official instruction, and keep the receipt. A broker can explain the schedule. A broker should not ask you to send the reservation to a personal e-wallet.