No-one elses prices will be acurate to you.
To find out a cost per service you must list everything you will use to complete that treatment.
Hat
Thong
Solution
Anibacterial cleaning wipes
ect..
Then price each item, for example if you buy 100 disposable hats for £10.00 then you would divide the cost by 100 to get a price per hat and write that next to the item on the list.
Hat ........................ 0.1
Thong .................... 0.50
Solution ................. 3.00
Anti bac wipes ........ 0.75
(*All prices above are totally fictional).
Some people use towels in the bottom of their tents so you have washing powder and electric costs where others will use sticky feet, the cost of insurance can differ greatly so a cost per service will be affected and some people are busier than others so that too will affect the cost per treatment for things like insurance.
When you have added everything you use to do the treatment including cleaning and insurance, rent, petrol ect.. then you will have YOUR cost per treatment.