Quality is one issue. Style is another. Experience is important too. A professional has done it before. No need to waste time reinventing the wheel, and in your business, time really is money.
Availability is another consideration.
Your cousin Jack with his Canon might be in Mexico on vacation just when you need that postcard shot done. Rates for professional photographers are very similar in all parts of the country. The cost of equipment is a major determiner of what is charged, as is travel, film and film processing. You are welcome to compare our rates with any charged anywhere. It's important to reserve a date so that we can plan for backup dates in case of bad weather.