When you start something new, you never know the unforeseen obstacles that can delay your project completion. It is not a big issue when you go for website design and can be planned beforehand. Take an estimated time from the agency for the completion of the project.
If you want to finish the project in a short time, then you may have to pay some extra amount nut it also does not mean that they can take long. After you are given a time frame, monitor it throughout until the project is complete. Hiring Verz Design means completion of project in a short time that too without paying much.