What does everyone think of a cloud mining service that guaranteed you would make your BTC back plus a percent. I don't know what the percent is yet. I just thought of the idea. Basically the contracts do not have an expiration date. After the contract pays its guaranteed percent you were given the option to repurchase. This gives miners a guaranteed profit and gives the service an easy way to finance hardware so that it can mine for itself.
It's not that easy from an ownership perspective. Your profit has to exceed what you would normally make mining, otherwise what's the point? You also have maintenance costs that you incur (power, etc) and you either pass that on to the customer through the price per share as a percentage or you pay for it yourself out of your pocket. So you have to set a price that A) covers costs (equipment + maintenance) B) is competitive and C) allows the contract owner to make a profit (contract earnings - maintenance/pool fees/etc) - cost of contract.