Hello Victor. Do not stop doing the following homework if you are ok with the price or sales pitch. You should run a company or personal background check on them and request recommendations, from trusted sources, about their expertise level, service quality, team working skills, time management and communication capabilities, handling of security/confidentiality/privacy factors, commitment degree, vision of long-term partnership, company values and culture, work examples, and so on. If you read information in the web about them be sure to check testimonials. Interview not only the sales people and general manager but also talk directly to the developers. Have fun and success.