If you're operating your business as a sole proprietorship in the United States, you don't technically need an EIN for the business – you can file taxes for your business along with your personal taxes. However, you may want one if you want to open a bank account for your business, or if you don't want your Social Security number to appear on business documents.
Everyone that buys a painting or has a nice photograph or a portrait made of their family may also need to have that work framed. Framing requires a specialized skill set that includes having craft-person talents, the ability to do simple carpentry, to know how to safely run a table saw, and have a good eye for pleasing aesthetic designs. You will need to understand color combinations and how to make a painting or a photo nicely framed to fit in well with the intended surroundings.
Driving for one of the two globally expanding app-centric taxi alternative services, Uber or Lyft can still be a fairly lucrative way to earn money as a side business idea on nights and weekends—working only when you want. But before you dive head first into this side business idea, do your homework and calculate the costs of extra gas, mileage, tires, wear & tear and usage on your vehicle—it's not a guaranteed business idea that'll turn a huge profit every weekend.
Martial Arts, huh? I teach too, and have found that when I want to offer a new class I give a free workshop. If you went around to the non-profits, churches and other type of groups and offer a free 1 hour talk on self defense with a question and answer period you’d get your name out there as the go to person to learn self defense. Set up a page on facebook, instagram on tips for self defense and invite people to follow you. 80% good info and 20% Hey hire me to train you. Bet you’d get a large following within 6 months. Let us know how it goes. Good luck