Is there a property service contract or a supplementary agreement first?

The property service contract comes first. According to legal customs and practices, the property service contract comes first, and the supplementary agreement comes later. This is because the property service contract is the most basic and important contract document, which stipulates the basic content, rights and obligations of property service and has legal effect. Supplementary agreement is a supplement and modification to the contract, which can only be carried out on the basis of the property service contract.