we have quarterly inspections too..bit of a change from our last real estate where we were lucky to have annual inspections! Lol.

I just do a 'normal' house clean- do bathroom/toilet, vaccuum and mop, tidy up Hayley's toys and have a go at weeding the garden. It's not spotless and I know it could be cleaner, but our agent is really lovely and she always comments how lovely the house looks so she's obviously quite happy with it! I think as long as it doesn't look like a pigsty and there are no holes in the walls etc then it should be fine..especially with quarterly inspections they can't expect you to go OTT 4 times a year cleaning the house, particularly when you have young children!