Non-itemized charges: Generally, when IT products and services are sold as a non-itemized package, the entire transaction is subject to retail sales or use tax.
Yes. Retail sales tax applies to a service contract or warranty sold to a consumer.
Professional services are generally not taxable in Washington State. However, some services are subject to sales tax. “Constructing and decorating real or personal property for others” is taxable.
Most US states don't mandate business licenses for independent contractors, but some, such as Alaska and Washington, do. Certain localities also enforce licensing requirements. This is particularly common in cities or towns with a business license tax.