Accounts Receivable (Tables)

9 Months Ended

Sep. 30, 2019

Accounts Receivable [Abstract]

Schedule of accounts receivable

	September 30, 2019			December 31, 2018
Billed:
Block sales	$	—		$	14,723
Construction services		1,306,567			1,619,498
Engineering services		333,230			400,877
Retainage receivable		544,911			543,417
Other receivable		37,526			7,706
Total gross receivables		2,222,234			2,586,221
Less: allowance for doubtful accounts (1)		(785,895	)		(839,895	)
Total net receivables	$	1,436,339		$	1,746,326
(1) The allowance for doubtful accounts is primarily due to unpaid billings on a contract that is currently in dispute.