I went to the millionaires center page and was scrolling through looking at the items for sale, whenever I hover over some items it says "not enough purchases" do I have to spend so much sp to unlock that item even if I have enough?
Also I noticed some items are available in user shops for way more. Can you buy cheaper and restock for that much more and actually have anyone buy those items?
Any item that shows up in the millionaire center is available for purchase as long as you have enough sP to buy it. The "not enough purchases" thing you're seeing is an estimated value based on prices that people have purchased the item from in user shops. If no one has purchased the item from a user shop recently, then it doesn't have any data to make an estimate and will just display that text instead.
As for the second part of your question, it can be hard to determine. If the items are available for cheaper in the MC, I think most people would probably purchase from there instead. Just because people have items listed for a certain price in their shop doesn't necessarily mean people will buy it for that price, or if it does sell eventually it could be sitting there for a long time before someone buys it. I don't think the MC is really recommended as a shop to try and buy things from for the sole purpose of reselling them.
Also, once the season changes the prices go up in the shop. So something overpriced in user shops right now, may be sold once the shop goes into another season. The price difference is 25% (if I remember correctly).
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