So nobody with only, say, 1 miner, would sell me a fraction of the hash rate of their miner?
Oh, there are a lot of people that do that.
They are called Perpetual Mining Bonds
On
https://btct.co/:
E.g.
TAT.VIRTUALMINE
DMS.MINING
PAJKA.BOND
Usually they are a bad investment though.
Atm difficulty increases a lot and dimishes the returns for them.
Only if you believe difficulty will drop/stay the same or they are cheap enough (do calculations!), it may be a good idea to invest in those.