What price does it make sense to insource manufacturing?

Revenues First Month of Operations: 10,000 units sold at $10 per unit. Second Month of Operations: 20,000 units sold. The first 10,000 at $10 per unit, and the second 10,000 at $8 per unit. Third Month of Operations: 40,000 units sold at $6 per unit. Remainder of the year 40,000 units per month sold at \$XXX? per unit Cash Flow characteristics: Goods are shipped at the end of the month are paid to the Company at the end of the following month by the customer. Cost of Goods Sold is made up of three components: Direct Materials - $2 per unit Direct Labor---\$3 per unit for the first two months, add 4 new mfg employee as a direct cost at $60,000 per year, $5000 per month starting the third month. Fixed Machinery and Mfg. machinery and space rental costs---\$10,000 per month, reduce to $7500 per month to reflect an equipment lease for a $500k investment in mfg. technology and a move to a new facility. Cash flow characteristics: Mfg. is now done by the company and all costs are paid month during the month that the goods are produced. Operating Expenses: the remainder of the company's expenses includes the following: Salaries for office staff and the Owner are fixed at $120,000 per year or $10,000 per month. $50,000 of the total goes to the owner Advertising is a fixed rate contract with an internet services firm which provides the company with secure servers, web analytics and Search Engine Optimization services for $3000 per month. Office Rental is a fixed yearly rental contract for the administrative offices which costs the company $4500 per month. Insurance is a fixed rate contract for insurance on the plant property and equipment is $1000 per month. Cash flow characteristics: All operating expenses are paid during the month that they are incurred. Ownership and Taxation: The Company is owned by a single individual who is paid a salary of $50,000 per year. The Company is organized as an LLC and is taxed as a pass-through entity which means that the Owner is taxed on her combined salary and the pretax income of the business. Appendix Continued: 1st QTR Appendix Continued: End of 1st QTR Appendix Continued: 2nd QTR Appendix Continued: end of 2nd Qtr. Appendix Continued: 3rd QTR Appendix Continued: End of 3rd Qtr. Appendix Continued: 4th QTR Appendix Continued: End of 4th Qtr. - Full Year Cumulative