Provisional & Formal Agreement
Provisional Sale and Purchase agreement is signed initially after you and the vendor both agree on the deal. It is a legally binding contract that must be fully observed and performed by the parties involved. You should seek legal advice whenever you are in doubt. For the usual items that must be included in a provisional agreement and other useful information, you can refer to the link below.
Formal Sale and Purchase Agreement should be drafted by a solicitor based on the provisional agreement. It contains terms that are more detailed and is intended to replace the provisional agreement. You can include any special conditions you want as long as they do not violate any relevant ordinances or contradict the terms of the provisional sale and purchase agreement.