Does $640 sound like a reasonable charge to instal...

Does $640 sound like a reasonable charge to install a standard garbage disposal? Normal cost is $185. We even bought the replacement disposal all we needed was the installation. Never ever have had an issue in over 25 yrs from previous replacements. The technician was there less than 2 hrs. Was told additional work was necessary to put in a longer electrical cord and pipe. Suspicious....be aware...before calling for service. Hope can resolve this reasonably. What a bummer for Christmas.