How to tell whether a price is fair
Ask for a breakdown. A normal quote shows what you are paying for: design, development, copy, SEO setup, support. If the price is a single number with no breakdown, that is a reason to ask questions. If it is suspiciously low, ask what is NOT included (copy, SEO and support are usually split off as “extras” after launch).
And conversely: if the price is high, ask for an explanation of what makes it up — a good provider will happily explain it point by point.