It's been in about 5 years.Will a scrub brush and detergent do it?

No grease down the drain , liquid laundry detergent is best to use .

A little move in basket with some of the following :  assorted felt furniture protectors for the wood floor, a sponge, cleaner for a glass top stove if there is one, a small bottle of hand soap,  a couple of packets of dishwasher detergent, maybe a dishtowel, and a roll of paper towels,  windex or such. 

This tenant sent me photos...yada, yada, the detergent tablet (recommended by the repairman) didn't even dissolve etc..  

Mix a solution of 50% bleach and water , add some dawn dish detergent in a pump up sprayer , hit the dirty areas from the bottom up , and rinse with a garden hose .

We created a brochure for our tenants explaining how to use the new front-load HE machines and gave each of them their first half-gallon of HE laundry detergent.   

Toilet paper, cleaning supplies, coffee, towels and sheets, laundry detergent, etc.  

People will use it during quiet hours, start a load of laundry and forget it, steal someone's laundry detergent, leave the dryer filter clogged, etc.

Shampoo, condition, body wash, hand soap, coffee, creamer, toilet paper, paper towels, laundry and dish detergent, copious amounts of sheets, pillow cases, blankets, etc.Nearly every Airbnb host I have talked to has lost money on cleaning fees, so there is another expense.  

Toilet paper, paper towels, bath soap, dish soap, laundry detergent, those scrubby things for dishes, dishwasher detergent.