It is the obligation of all potential web developers to give their clients with references even without being asked. However, this could be the opposite with some developers who are never willing to give out references. If a developer denies you with references, it is a red flag that whatever he/she provides is not to be relied on. Also, get a developer who gives you the chance to give your wishes for the design. It is a surprise that some developers are never concerned with their customer's budgets but adds extra features to make the costs increase. This only shows how selfish the web developer is to fulfill his/her wishes and not that of the customer.