5. Property and Equipment (Details) - USD ($)	Mar. 31, 2019	Dec. 31, 2018
Property and equipment, gross	$ 3,770,567	$ 3,672,580
Accumulated depreciation	(2,754,712)	(2,636,267)
Property and equipment, net	1,015,855	1,036,313
Computers, Software and Office Equipment [Member]
Property and equipment, gross	2,024,205	1,937,987
Accumulated depreciation	(1,597,372)	(1,508,104)
Property and equipment, net	426,833	429,883
Machinery and Equipment [Member]
Property and equipment, gross	169,515	167,731
Accumulated depreciation	(106,220)	(99,900)
Property and equipment, net	63,295	67,831
Vehicles [Member]
Property and equipment, gross	148,580	153,927
Accumulated depreciation	(100,394)	(120,728)
Property and equipment, net	48,186	33,199
Furniture and Fixtures [Member]
Property and equipment, gross	385,605	381,248
Accumulated depreciation	(293,744)	(284,410)
Property and equipment, net	91,861	96,838
Leasehold Improvements [Member]
Property and equipment, gross	1,042,662	1,031,687
Accumulated depreciation	(656,982)	(623,125)
Property and equipment, net	$ 385,680	$ 408,562

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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