License for Affiliate Marketing

[Laz]

I am starting an affiliate type of ecomm that will also include drop shipping, etc.
I am planning several sites for related themes in order to penetrate similar niche markets, each with different site names. The laws here are confusing (Washington)as to licensing requirements. I get different answers on different days by the various licensing departments so I come to forum members for some insight.

By having an umbrella structure/sole proprietor, is one license enough at the state level or do I need to acquire one at the local level as well. I have heard and read conflicting information on this.The business will be ecomm/emarketing only and not really requiring permanent building structure in any way. (no stock/no office) I will be mobile soon and check in on my sites from various locations.

Can anyone please offer some thoughts on licensing for this type of business that has many websites?