Genesis Mining, one of the legit cloud mining companies has launched their pre-sale open ended bitcoin mining contracts today with start date being mid-March 2018. I have been with Genesis since Aug and I haven't been disappointed at all. Occasionally, the payouts go missing in my dashboard, but eventually the amount of BTC I receive still remains consistent.
To register and get a 3% discount or more use "Dmf8qK" via
https://www.genesis-mining.com/pricing#bitcoin-mining
Take a look at their mining farms via their video
Here's their CTO explaining the process of building a single rig
There are a number of scam cloud mining sites out there.
But, with Genesis you can be really sure and rest assured about their professionalism and legitimacy.
Feel free to reach out to me on Twitter (https://twitter.com/rmncryptosaint) if you have further questions about Genesis or any other Cloud Mining options.