When should I do a walkthrough if the apartment is still occupied?

I’m. Newer agent and to get started I’m working on a couple of rentals. Doing walkthroughs has been easy so far because all of the rentals were vacant. We could make an appointment at any time and do our walkthrough. I have a rental where we have a verbal agreement and they want to move forward with my clients. However before we sign the lease we would like to do a walkthrough make sure that everything is working as it should. Take pictures of any damage the previous tenant has caused to the property. My problem is that the current tenant moves out at the end of the month and my client would start at the beginning of next month. I’m having trouble figuring out when to do the walkthrough. I have asked other agents in my office but I either have gotten as a response. That they don’t do walkthroughs for rentals or that I should just do a walkthrough while the current tenant still occupies the property. Has anyone had a situation like this before?