Below is Part 3 of the email I received from Dave. I am posting it for everyone to learn from, with his permission.
It didn't start off easy for me at the flea market. My first week, I paid $125 in rent and took in $148 from sales. It was hard for me to sell the donuts. People didn't know what mini donuts were, and to be quite honest, I don't even know if people knew what I was selling. I would put a sample cup of donuts on my coffee table to try to sell them, but still, I would only move maybe 10-15 bags (I sell them in bags of 13) in a day. I started up my ice cream machine, and blew the whole flea market out of power two weeks in a row. There wasn't enough amperage to run it, come to find out. I was told I couldn't run it off the flea market electricity, and would have to use a generator if I wanted to sell ice cream. I didn't want to bother with that, so sold the machine back on ebay. I only had 6' under my fume hood to work with, and there didn't end up being enough room for both my donut machine and the fryolator where I was going to fry the ribbon fries. So I had to pick either ribbon fries or donuts, and I chose donuts because basically it's an early morning market and I thought they would go better. Sales for year 1 were bleak. I thought I was going to have to go out of business. I was discouraged, but figured I'd keep plugging along. Year 2 came and went, and my numbers had improved some, but still it was not to the point where I wanted it. I tried adding menu items like cheese steak sandwiches and sausage and pepper sandwiches, to increase revenue. I found that there was a lot of waste with those items (rolls can only be re-frozen so many times, etc.). Plus, mark up was only 100%. I was putting $3 into a $6 sandwich.
For year three, I decided I'd focus on my most profitable items, and market the hell out of them. Donuts cost me 50 cents a bag to make, and I get $3 for them. Smoothies cost me $1.12 and I get $3.50... an airpot of coffee costs me $1.13 to brew, and I get about $10 out of it by the time it's sold. I called up my smoothie company (Island Oasis) and asked for any free promotional material they could send me. Companies like this often give away their promo material, because they know it's going to help you to sell more of their products, so it will bring them more sales in the long run. I got a nice tin sign, a huge banner, and a menu board with changeable flavor slats from the smoothie company. Then, I went to decalzone.com and ordered some big, bold 9" lettering that says FRESH MADE MINI DONUTS. I noticed that my trailer was the only trailer at the market that you couldn't see what I was selling from across the field. I wanted to change that. I put up those letters above my windows so you could read it from across the field.
Here is a picture of my trailer after making those improvements:

Simplifying my menu to include only a few items (my most profitable ones) allowed me to streamline operations and to serve customers faster. My business really started to pick up. I think that people really didn't know what I had up till that point. So take that as a lesson... people must be able to see what you are selling from afar. When people buy your products, they must be something that makes them want to come back. I serve the only brand name coffee there... Green Mountain. I bet I sell more coffee than all the other food vendors combined. People love it. My mini donuts are good because I try to look into any problems people may bring to my attention. For example, Little Orbits says to fry the donuts at 375 degrees. The fact of the matter is, the cool donut batter cools down the oil if you set the machine at 375, so you are actually probably frying at 10 degrees below that for most of the time, since you are constantly depositing cool donut batter into the oil when running the machine. The trick is to set your temp knob half way between 375 and 400. That way, when you factor in the cooling of the oil from the batter, you are actually frying at around 375. If you fry at too low a temperature, more oil gets absorbed into the donut and it comes out greasy. Also, it is best to use oil that is solid at room temperature to fry the donuts in. I use Wesson MFB Shortening. It is a little harder than Crisco in consistency. I melt it down in my hot fudge warmer, which I keep behind the donut machine, and ladle it into the trough as the level gets low. If you use oil that is liquid at room temp, more of the oil will get absorbed into the donut. People don't like greasy donuts!
Thanks again Dave! Tomorrow Dave will talk about about how many bags of donuts he sells in a typical day, how to start your day off as a vendor and some advice on signage for you trailer.
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