Research: Buying from an online store

I went on to conduct some research on professionaly made designs, i was quoted £10.99 for one website, (TSHIRTSTUDIO) and £12 for another website. These prices would not be appropriate for what i am trying to achieve. In reality i would like to keep costs of making the t-shirt uned £5 in total, and although this method provides everything ready-made, it is far too expensive, and will only result in me making a loss.

There were options to buy the t-shirts from professionals in bulk, however the discount was only 10%, and for over 100+ t-shirts. I am only looking to produce 20 at most, so again this is very much not appropriate.