Long Drop-In Visits & How to price?

I had someone inquire about drop in visits for their 2 dogs. 1 is 2 months old & the other is 1 year & some months old. They are wanting 1 drop in visit per day for about 2 hours (4-6pm).

I have never done a drop in visit longer than 45 mins so I am unsure of how to PRICE this visit. My drop in visits for up to 45 mins is starting at $15 for 1 dog and $5 for each additional.

Can some one give me some advice on how I could price this?

The dates are for 12/27, 12/28, 12/29, & 12/30.