Don't forget, we often will gladly help people out with larger transactions (and have done so MANY times over the years), but acting as an intermediary with larger transactions for folks. Sure we have to charge a few pennies for our time/effort and for optionally letting someone use a Credit card, but we are then able to verify both the item being sold and the funds being used for purchase. Not something we openly advertise, but certainly something we frequently do.
But there is also the aspect of responsibility for due diligence as well. That may sound harsh, but often times when something sounds like a great deal it isn't. That's just a cold/hard fact of life, especially with avionics. Sure, we sometimes have screamin deals ourselves (and frequently sell on this site as well as online auction sites, etc..), but even then they aren't fire sale type deals either and I hope we've worked pretty hard over the years to earn the trust of both buyers and sellers.
Just my 2 cents as usual.