The cool part - the price to run 72 PH for a day would be around 14 BTC on Nicehash, meaning that you can get a block (probably) but would lose money on it. Which is the whole point of cloud mining being a questionable venture - why would anyone sell something (hash power) cheaper than they could use it?
While I agree with your conclusion, I feel it only responsible to point out that "rentals" and "cloud mining" are different concepts and implementations (and that cloud mining is, imo, a cancer to the entire crypto space).