Where can I find the procedure to record an advance to a building contractor for the renovation of premises
Recording a variety of transaction types is made simple with QuickBooks Online! While you have tons of tools at your fingertips, the best tool in this case is your accountant.
I recommend reaching out to an accounting professional to consult with them on the best method for recording this type of transaction. This is the best way to get the most accurate advice possible, and ensure things are being recorded properly. If you're not yet connected with an accountant that's trained and certified in QuickBooks Online, you can reach out to one here: Find a ProAdvisor.
Once your accountant advises on the correct method for recording this type of transaction, our tech support team would be happy to explain how to reflect this in QBO. You can reach out to our agents here: Contact us.
I hope this helps. In the meantime, here's a similar question from the US Community that may give you an idea of how to get started: How do I enter an advanced payment to a supplier? Keep in mind that the tools may vary since this is an American resource, but it's just going to give you a few ideas in regards to the accounting aspect of the task.