First things first, always check their website and try to understand how they deliver their services, the types of SEO practices they use, pricing scheme and a lot more. Then, proceed forward by having a good look at their portfolio, check the clients they have had and the clients’ websites as well. If they don’t have a portfolio ready, then steer clear from such companies. Then, look for client testimonials. Check what the clients have to say about the SEO Company, check the authenticity of those testimonials, check if there is any way to get in touch with those clients and get feedback. You must also consider if the company offers affordable seo services to rank higher.
Also look out for the factors if they overpromise as nothing is set in stone when it comes to SEO. Check if there is any way you can get in touch with them. Check if they get back to you in time and there is always somebody available when you want to talk to the company on learning how their SEO process works. Also ask them the person who will be responsible in handling your SEO services. Because if something goes south, it will do more harm than good. You need to stay on a safer side when it comes to SEO.