A trustworthy webmaster should be able to clearly explain their process, including how they handle security patches and software updates.

Look for at least 15 reviews on platforms like Google or Facebook with an average rating of 4 stars or higher.

Google Webmaster Trends Analysts Q&A Interview - Aleyda Solis

If the "About Us" page mentions a different company name than the homepage, it may be a template-based "front" for an overseas manufacturer.

Use of services like "domainsbyproxy" to conceal ownership information can be a warning sign.