7. COMMITMENTS AND CONTINGENCIES Lease obligations   The Company rents office space under an operating lease agreement. The lease expires in August 2017 and provides for an option to renew the lease for an additional four years. In the normal course of business, it is expected that this lease will be renewed or replaced by a lease of a similar property. The lease provides for increases in future annual rental payments of 4% per year. Under the lease agreement, the Company is also required to pay monthly operating expenses of approximately $748. The Company has a sublease agreement with a related party as further discussed in Note 10. The following table represents future base rent payments, sublease income and the net lease commitment for each of the years ending December 31, Minimum Lease Sublease Net Lease Commitment Income Commitment 2014 $ 48,788 $ 29,220 $ 19,568 2015 50,739 13,336 37,403 2016 52,769 - 52,769 2017 31,488 - 31,488 $ 183,784 $ 42,556 $ 141,228 Rental expense for office space was $72,361 and $71,700 for the years ended December, 2013 and 2012, respectively. As further discussed in Note 10, rent expense reimbursements were paid to DOSA Consulting, LLC ( DOSA ) which is a consulting firm owned by the Company s CEO. Columbus Project   Pursuant to the option assignment agreement dated March 30, 2007, as amended August 8, 2007, the Company granted a 5% net smelter return royalty to NMC, one of the principal stockholders of the Company. The Columbus Project is further discussed in Note 3. Red Mountain Project   Pursuant to the option assignment agreement the Company granted a 5% net smelter return royalty to NMC, one of the principal stockholders of the Company. The Red Mountain Project is further discussed in Note 3. Stand-by letter of credit   In June 2011, a financial institution issued a stand-by letter of credit to the BLM for up to $175,000 on behalf of the Company. The stand-by letter of credit was issued to guarantee the Company s compliance with reclamation bonding requirements. The letter o