19. Commitments and Contingencies Operating Lease Commitments The Company entered into property and equipment leasing arrangements that expire at various times between August 2019 and March 2029, with optional renewal periods. Minimum lease payments range from $ 1,000 to $ 28,000 per month and may require additional rent to cover a proportionate share of taxes, maintenance, insurance and other shared expenses. Rents are generally increased annually by fixed amounts, subject to certain maximum amounts defined within individual agreements. Base rent expense under these operating leases for the years ended December 31, 2017 and 2016 were approximately $ 877,900 and $ 865,500 , respectively. In March 2017, the Company entered into 10-year lease agreement for a 14,382 square foot facility to accommodate growth and operational requirements in Columbus, Ohio. In late May 2017, the Company moved into the new Columbus, Ohio facility. The lease agreement includes six (6) months of free rent from June 1, 2017 through November 30, 2017. Thereafter, the lease requires monthly minimum rent of approximately $20,700, of which $10,200 covers base minimum lease payments and $10,500 covers estimated annual operating expenses and real estate taxes. Base minimum lease payments are subject to an annual escalation of approximately 3.5% beginning on October 1, 2018. The term of the lease expires on September 30, 2027, unless the Company elects to use an early termination provision that is available in October 2023. Any early termination election would require an immediate payment of a fixed penalty that may range from $260,000 to $265,000. During the year ended December 31, 2017, the Company closed three offices as part of its organizational restructuring activities and did not incur any significant lease termination costs. Future minimum payments by year (excluding related party leases) required under remaining lease obligations (including lease modifications as further described in Note 21) consist of the following for fiscal years en