Either the company is a Limited Liability Company or it's a Corporation. Aside from that, any Company having been established under State law can enter into contract. Having an attorney can help you avoid making contracts that are defective or leave out key provisions that later you may wish you had. I'd recommend you sit down with a Business Attorney licensed in Washington State (easily found on Avvo.com) and sort out how your Company can best obtain and enter into contracts where the Company's business and finances are protected. Good Luck!
It sounds as though what you have is a limited liability company that will be treated as C corporation for federal taxation purposes. For state law issues, such as contracts, it is and should be treated as a limited liability company. The limited liability company can enter into contracts subject to any limitations in its operating agreement; if you do not have such a document, you need to get one.
Any experienced business lawyer in your area can assist with both complying with the limited liability company statutes and for contracts.