There is a simple formula to find out your turnover rate.
Your turnover rate depends on a number of things like, the quality of product, your ability to market and advertise this product effectively, your personal people skills. timely and effective responses, knowing when to push a sale and when to hold back, your competitors affect on your consumer, etc, etc, etc.
What you could do is run a beta mailing program to see the results of your efforts.
Here is what you will need to keep track of:
The number of flyers you send.
The number of responses you received from these flyers.
The number of sales you made from those responses.
Let's say you mail out 100 flyers.
Out of those flyers you receive 18 responses.
Of those 18 responses you are able to close on 4 sales.
Your ratio would be 50-9-2 or it would take you 25 flyers to complete 1 sale.
This is called your sales turnover ratio.
Professional sales strive for a 10/4/1 ratio. Or 10 flyers to complete 1 sale.
You can use this formula for cold calls, door to door, or even email.
One thing to consider is that it is always good when you can find out exactly why someone decided on using you or turned away from using you.
This can help to raise your turnover rate as well.
Finally as a note of interest I tried to market services via flyers and mailings at one point. I dropped and mailed over off 350 flyers and recieved no responses.
I put an add in the paper for one week and recieved no responses.
Later I read that it takes a consumer hearing about the same product at least 6 times before they make a decison.
I put an add in a local paper for an entire month, and was able to close on 4 calls, which made a small profit. If I would have continued on my methods I would of been able to tweek my turnover rate enough to increase my profit, but I was more or less testing out a market to get a understanding of how things would work, and was not interested in expanding on that paticular portion of my business.
You must understand your consumer, appeal to his needs and fears, rise above the competitions offerings to be any where near successful.