How detailed should the contractor agreement be?

If you are considering using a template for your independent contractor agreement, you should view it as a starting point. It can be a good way of finding boilerplate provisions that are going to be in just about every agreement. Unfortunately, because they are templates, you run the risk of leaving out important details that may apply to your situation. Additionally, the template might not go far enough in protecting interests that you specifically need to have protected. Think of it this way. Template agreements are usually so general, they will probably be valid in almost every state. Consequently, by being general, they usually leave out key details that would apply in your situation but not in other contractors' situations. You should always consider having an attorney review your agreement to make sure that the agreement meets your legal needs and that it is legally binding in your state.

There are no set fees that are in an independent contractor agreement. Generally, what is covered are the fees or costs associated with the work or project and they may also include expenses incurred related to the work or project, such as travel and/or accommodations.

There are several potential pitfalls that can be mitigated or removed by addressing them in the contract. These include: whether the contract calls itself an independent contractor agreement but yet fails the test for an independent contractor and therefore brings in matters such as workers compensation coverage (depending on number of employees), liability for contractors acts or omissions, unemployment tax, tax withholding v 1099 and several others. These can be eliminated via proper drafting.

You're correct that your agreement should be fair and beneficial to both parties involved. Often, however, when an independent contractor receives an agreement from a company, that proposed agreement has been drafted to be favorable to the company, because that's the company's primary interest. In order to ensure the agreement is fair and equitable, you'd need to identify the business and legal provisions that are drafted in a way that protects the company but not you, and either strike those provisions entirely (if the terms are unreasonable), or suggest they be written in a mutual form. Some common examples of these provisions are warranty disclaimers, indemnity, limitation of liability, and exclusivity.

The terms that you write in an independent contractor agreement should, first and foremost, protect you/your business and give you the advantage in the relationship, if possible. While some such contracts may have an end date, that's not mandatory; but be sure to give yourself/your business the right to terminate the contract when you want to, without cause. Leave it to the contractor to negotiate better terms than you propose, on behalf of the contractor - that is not your job. I recommend that each of you use your own attorney to review the agreement prior to signing. And, by the way, ContractsCounsel.com has numerous documents available for purchase, and it's very likely they offer a boilerplate of this type of contract, vetted by WA State attorneys.