Although a virustotal scan says the site is clean I'm not prepared to visit it to find out if there's an office address. I would expect a legit company to register its domain using its office address, but a who.is check shows its hiding its registrant name and address behind a service in Panama. Anyone asking for large sums of money while hiding their identity isn't worth trusting. There's nothing to stop them disappearing with the money.
http://who.is/whois/cryptocoinmachines.com
Domain Name: CRYPTOCOINMACHINES.COM
Registry Domain ID: 1899611886_DOMAIN_COM-VRSN
Registrar WHOIS Server: whois.enom.com
Registrar URL: www.enom.com
Updated Date: 2015-01-31T07:17:44.00Z
Creation Date: 2015-01-31T15:17:00.00Z
Registrar Registration Expiration Date: 2016-01-31T15:17:00.00Z
Registrar: ENOM, INC.
Registrar IANA ID: 48
Reseller: NAMECHEAP.COM
Domain Status: clientTransferProhibited https://www.icann.org/epp#clientTransferProhibited
Registry Registrant ID:
Registrant Name: WHOISGUARD PROTECTED
Registrant Organization: WHOISGUARD, INC.
Registrant Street: P.O. BOX 0823-03411
Registrant City: PANAMA
Registrant State/Province: PANAMA
Registrant Postal Code: 00000
Registrant Country: PA
Registrant Phone: +507.8365503
Registrant Phone Ext:
Registrant Fax: +51.17057182
Registrant Fax Ext:
Registrant Email: Email Masking [email protected]