Contracts vary, if you watch the video it shows different prices for different mining. I recommend probably minimum of $500 to get started. At that point you can add to it as you wish. Major point, SHA-256 contracts are "lifetime" as long as profitable and the others are just 2 years. Can use this code for 3% off -

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My link to GMhttps://www.genesis-mining.com/a/573320