Selling blood….there are very few companies that buy your blood. #1 reason being MANY people willing to sell their blood are not the type of people you want to receive their blood, ie drug addicts (not everyone). And if you can find a company willing to buy your blood you can only give it every 56 days (for whole bood). The most common blood product that is bought is plasma and you can only do that every 28 days (in New York state …which won’t buy blood anyways).
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The best part about this is that you don’t even have to ever touch the actual product, nor do you have to spend a dime on manufacturing these products. They do all the work for you. You just upload the design, choose the items you want your design to be on, and they’ll handle the rest (i.e. manufacturing, payment, shipping, and handling, returns…).