I also brought my two cats over by myself this past March, and it cost me all totaled $2,597.92. That's vet visits, buying the kennels, airfare, customs fees, etc. I'd say your quote is definitely a bit high for just one cat, unless you REALLY just don't want the hassle. And it is a big hassle! But totally worth it.
Your friend can definitely drop them off at the airport for you, as long as all the paperwork is done and the airline knows that's the person who's sending them to you. My sister took my cats to the airport the day after I left, and since the paperwork said she was the consignor, there weren't any issues.