Good Camera

A used Canon Powershot (like an A590) with a macro lens ($4) and lens adapter($7) will take pictures pretty much inline with the much more expensive Cannon Rebel and fancy macro lens I bought for a fraction of the cost. I bought my gear because I already use Canon for shooting film and have all the toys.

You can acquire the whole lot with a mini tripod under 100 dollars and use it only for dedicated coin shooting without breaking the bank. the series have good features for setting up for manual shoots and leaving it on fully automatic will still result in good shots.