Most mining rental websites will charge you a price above what you can expect to earn by using the hashpower
Yes, at least it currently seems so.. The person who borrows money does not only have to take the loss by renting hashpower but also has to pay the interest rate..
Maybe times will change concerning cloud hashing services..
hashpower rental sites will have no reason to charge less then wheat it would be expected they would earn by mining themselves.
It really only makes sense to rent hashpower if you are trying to test something/do some kind of research or if you are trying to attack a pool/altcoin
I think thats too easy. It is also a question of collecting enough money to be able to run rigs. As a provider you can use new revenue to buy new rigs and scale it up this way..
Besides that I don't think it is clever (from the view of the provider) to put all money on one bet. It also about risk diversification to rent hashpower to others. Especially because the development of prices and exchange rates is NOT predictable as you can see on the last two days upturn..