leasing

Hello!
I have a question regarding the leasing topic, more specifically- commission income.

From the perspective of the lessor, when the company charges the commission (for example: 1% of the equipment cost for helping with documentation or performing all the required procedures with the client) how is this income recognized? Is the whole commission income amount recognized when the service is performed or recognized throughout the leasing period?

There is not much information about leasing from the lessor perspective and i couldn’t find any information in IFRS. I know this will not be on the exam, i am just curious