If a company wants to truly develop a product cost analysis, they would need to
determine the cost of everything.
Sure, you can say that you can't factor in the cost of your buffer, but you really should.
You should look at the initial cost of the machine and then determine the approximate
lifetime of the machine under normal use. Then you should add in regular maintenance
and upkeep on the machine (How often you get it lubricated or purchase new pads).
While there is some variance with equipment, it could have a defect, or you could drop it,
you should not let that stop you from factoring in your equipment into cost analysis.
As for product cost varying, YES this is difficult to calculate. If you do want an accurate
analysis, you must go the extra steps to determine this also. If you can get Product A at
40% retail and Product B at 10% off retail, just the fact that you get different prices for
different products should not hinder your analysis. Just determine how much Product A
that you use for a normal Car. Then you determine that you use X more product for a truck
rather than a car. Then you must determine your client load. If you have 75% trucks, only
10% cars and 15% minivans, then you can determine your average cost for Product A per job.
If you do this for all of your products, then you can get an accurate analysis.
If you just wish to determine a few factors, your analysis will not be complete. This is not a
very big deal, as you should have some margins to work with. All I am saying, if you want
a good cost analysis, you can not make excuses of why you can't calculate things.
Do the best that you can, add in a margin of error and then add in a certain percentage just
for things to go wrong. You should have that pad built in that allows you to account for
bottles to be broken, towels to be dropped and product to be spilled. Again, this is not a
neccessity. However, responsible owners will always get as close as possible. You are the
best person to be able to approximate your business. For me, I would always want to
approximate my costs to be higher, rather than lower. This protects me and my business.
Everything that goes into the detail is your "supplies". You should gauge your average distance of travel for a detail and put gas and mileage into there also. How else would you know if all of the little things of your business are eating away at your profits. You should
also know how gas prices affect your margins. How much will you hurt if gas prices go up
25 cents? While you might not know, you should. If gas goes up, you should know how
much that you need to raise your rates to offset this, or at least be knowledgeable about the cost so that you can decide if you can just "eat" the loss.
There is no variable cost between an f150 and a prius. It is only the cost of YOUR vehicle,
the age of the vehicle and the cost of upkeep and maintenance. You would need to factor in both an f150 and a prius if you used both for your business at different times. If this is the case, then you would determine what percentage of the time you drive the truck, and what percentage of time that you drive the car.
Saying that you can't compute something into the analysis is a bit of a "cop out".
While factoring everything into the analysis is not the easiest thing, this is the only way that
you will get a true view of your business. If you take the steps to account for everything that goes into your business, then you will gain valuable knowledge about how you operate.
Speaking of operation, most successful businesses also factor in the cost of marketing into their operating cost. One thing that you should factor is the cost of acquisition. If you were able to determine that it cost you 3 dollars to gain a customer, then you should also factor that into your cost.
Sure, having returning customers throws this number off.... but you can determine that also, it is just more analysis. You would then need to analyze the percentage of your customers that are new versus the ones that are returning customers. If you have an acquisition cost of 3 dollars per customer, but half of your customers are returning customers, then you should be factoring in a $1.50 acquisition cost into every single one of your details. This acquisition cost factors in business cards, marketing and your website fees.
It is only when you factor in everything, that you can see the true cost of all of your products.
It is similar to purchasing a product, but not factoring in shipping and handling.