capabilities. The amended completion date is August 29, 2022. As of May 6, 2022, we have negotiated contracts for the purchase of automated assembly equipment, molds, and molding equipment, as well as portions of auxiliary equipment, for approximately $64.2 million. We have also received a temporary certificate of occupancy for the $6.7 million 27,800 square foot controlled environment which was funded by the U.S. government under the original agreement. In addition, we have substantially completed the additional controlled environment space required under the May 12, 2021 amendment. Finally, we have received the certificate of occupancy for the new $5.9 million 55,000 square foot warehouse which is our financial responsibility.
As a result of the COVID-19 pandemic, we have faced and continue to deal with the logistical challenges of sourcing raw materials and finished goods, particularly finished goods from China. We utilize multiple transportation providers to ensure we can meet our delivery schedules, but we are subject to the global supply chain and its complexities. To date, the freight challenges have neither caused a loss of customers nor a cessation of production. However, freight costs have materially increased. The increase in freight costs has significantly impacted our cost of manufactured product, and we expect this trend to continue as long as the global supply chain challenges persist. These cost increases are not unique to our business, but the fact that a substantial percent of our prior period sales were related to orders from the U.S. government with reimbursed freight costs will affect comparability of 2022 costs and margins to prior periods. In addition to increased costs associated with the global supply chain, we have had challenges sourcing transportation. There is also possible risk from the political environment in Europe and Asia. We believe that with our current levels of products on-hand and our ability to produce domestically, we are positioned to continue to operate and meet the needs of our customers currently. Other factors that could affect our unit costs include increases in tariffs, costs by third party manufacturers, and changing production volumes. Increases in costs may not be recoverable through price increases of our products.
Other factors which could have a material impact on our business include COVID-19 booster shot recommendations, flu shot campaigns, and inefficient domestic distribution networks. An increase in the frequency or necessity to administer additional COVID-19 boosters or flu shots is still uncertain and may not lead to an increase in our product sales.
We have entered into an agreement to expand our existing administrative offices by 14,000 square feet. We currently expect that the cost of expansion will be approximately $5.6 million. The expected substantial completion date for the new office space is October 2022. To date, we have spent approximately $2.0 million.
As detailed in Note 4 to the financial statements, we held $18.7 million in debt and equity securities as of March 31, 2022, which represented 17.5% of our current assets. Such amount includes unrealized gains on investments, as well as an additional $2.0 million cash investment during the first quarter of 2022. We continually monitor our invested balances.
In response to, among other factors, the global COVID-19 pandemic, our delivery orders from the U.S. government, and the TIA, employee headcount and related salary and benefits costs have increased significantly. As of March 31, 2022, the Company employed approximately 269 full-time, part-time, and temporary employees. This represents approximately a 29.3% increase in our workforce since March 2021 and compensation costs increased 25.6%.
As a result of our completion of the original U.S. government delivery orders and the progression of the TIA, we continue to monitor our current level of operating expenses, including the overall impact of our staffing structure.
Effective June 4, 2021, we entered into a repurchase plan (the “Plan”) for the purchase of up to $10 million of our Common Stock. Under the Plan, open market purchases of our Common Stock commenced June 18, 2021 and 1,087,145 shares were purchased through the Plan’s termination on April 14, 2022 for an aggregate purchase price of approximately $8.1 million. We terminated the plan because our stock price appears not to be correlated with our economic performance at this time.
Historically, unit sales have increased during the flu season. Seasonal trends in 2020 and 2021 were less pronounced due to demand related to the COVID-19 vaccine. With the completion of our delivery orders from the U.S. government, flu season orders may have a more pronounced effect on 2022 revenues.