Yours is one of those questions that almost demands you do the research for yourself. There are so many variables that no one but you could possibly know what would be the cheapest for you. What country do you live in? It might cost only $25 dollars in China, but the identical motor could be $300 in the U.S. What about shipping charges, specifications , and on and on.I could tell you that I bought one for $10, but how would you know that is so and even if that were truthful, it might be different for you because of various fees, dealer profit, taxes. Moreover, it just seems to be a bit of laziness on your part, asking someone else to do the research you should be doing.A more reasonable question on your part would be something like, 'I have found these motors and these are the specs and here is what I want to do with it, can someone advise me which would be better for this purpose?"