In a real way, a dojo refers to the people training together, not the building, the instructor, or the business. When visiting a prospective studio or dojo, do your best to look at who is training. If they are sincere in training themselves and create a space which encourages others to be sincere about their own training, it is likely a good place. If there is competition or heavy focus on appearance or attitudes, it might not have the martial arts focus that will empower you to focus on yourself. Find somewhere were you can be yourself while training, and where you can train to better yourself in line with who you are.