If the company that is interested has access to printing facilities, it can probably get them done at very competitive rates and buy the blank t-shirts at wholesale prices, too.
If you do it yourself, you'll have to make sure that the quality of the t-shirts and printing is what your outlet expects, otherwise you could spend a lot of money for nothing. It also depends on the quantities that they expect you to supply. As a general rule, the bigger quantity you buy and have printed, the cheaper they are. That's how you increase how much you make.
Negotiate with the outlet about your return if they do everything for you. Bear in mind that they, too, get the benefit of quantity discounts.
Try approaching Business Link for free help from one of their advisors on what you're planning to do. Have a look, too, at companies that provide corporate gifts or incentives. Most of them print t-shirts, which will give you an idea of prices.
The printing is called SILK SCREEN PRINTING. Once you have the design and ready to print on the T-shirt, you have to set the printer options to MIRROR which will print the image in reverse. Then when you iron it on, it will reverse again and show correctly. Otherwise if yo don't do that, the pic, the wording will come up written backward.
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