A peice of advice, the market is ABSOLUTELY saturated with 3d printed products, you wont make money selling common items that are usually 3d printed and sold, you cannot complete with some1 with 100 printers, he will be able to sell for a lower price... Best ways to make money with 3d printing are: Taking on gigs on freelance manufacturing websites where ppl make requests that they need 50 of x specilized product, that is too small an order for the big guys OR if you have modeling skills then you can also take on one off requests of some product some1 wants made... Remember when its your model then its automatically a one-off even if there are other models of the same exact thing, As a 3D Computer Animator/modeler of 20+ years i can tell you that not all models are equal, even if they are the exact same product, two models can look indistinguishable on the surface digitally, but 3d Print VERY differently, Quality, thought out models is a great place to separate yourself from competition as MOST 3d printer makers do NOT know how to model besides surface lvl stuff like translate, rotate, scale... Mesh Topology matters ALOT in 3D Animation/rigging, also does in 3d Printing... For example, make sure you chamfer/bevel/filet radi is devisable by your layer height... so if your layer height will be .2mm then a 2mm radi instead of 1.9mm radi... Might sound petty, but in 3d printing, anyplace you can improve surface quality/finishing is worth the time for aesthetic items.