1. Quality of Print: This is one of the most important factors. Check the quality of their past work, their colour accuracy, image resolution, and the sharpness of the designs.
2. Material Quality: The materials used should be durable, safe, and suitable for the surface where you want to place the sticker. Look for companies using eco-friendly, UV-resistant, and weather-proof materials to ensure longevity.
3. Design Variety: A good company will offer a wide variety of designs to cater to diverse tastes. They should have options ranging from simple shapes and colors to complex illustrations and photographs.
4. Customizability: The company should allow you to create custom designs if you wish. They should be able to handle everything from simple text to complex graphic designs.
5. Customer Reviews: Reviews from previous customers can provide a lot of insight into the company’s reliability, quality of work, and customer service. Look for positive reviews on both the design and printing aspects, as well as how the company handled any complaints.
6. Price: While you don’t want to compromise on quality, you should consider your budget. The company should offer competitive prices. Check if they offer any discounts on bulk orders if you’re planning a large project.
7. Customer Service and Support: The company should be easy to communicate with and respond promptly to any inquiries or issues. They should be willing to work closely with you to ensure that your vision is accurately represented in the final product.

Remember, the best company for you might not be the best for everyone. Consider your specific needs, including the scale of your project, your budget, and your design requirements.