Is it spongy floor or just normal with age?

Hi. I've been looking at 2nd hand 4/5 berth tourers for a couple of weeks. It will be a first van for my family.

I have seen one I like and have been to check it out twice. I've had a good look for damp, checked all doors, wondows, blinds hinges etc.

I have one query regarding the floor in front of the kitchen area. There is a slight depression in it. I wouldn't say it feels spongy, just indented.

Is this a problem or is it just to be expected in a 1998 van in a high traffic area of the floor?