Too bad it has to be a Quad Cab, my local dealer has an '05 on his lot, 4.7, 4x2 with 66k miles on it, looks to be in about mint condition for $7995 and an '06 with 43k miles for $9995.
Hell it's a shame you can't come up with a little more cash, they got an '08 with the 310 HP version of the 4.7 with 29k miles on it for $14,995.

 

According to KBB, my 04 5.7 with 73k comes to 11-13k on a trade and 14-16k on a private party. But I could never let mine go for that with all i have invested.....LOL

On a side note, I watched (Ebay) a 07 MC CTD dually (5.9L 24v), auto and had 200k on it sell for 15k and it was in Fayetteville, GA

 

It's gotta be a Crew cab as I have a wife and two growing sons (one's as big as me already), and I do not want a Dually, nor do I have a need for one. You can snag a late model Dually pretty cheap, but that is because the demand is so much less. I think I'm looking for what everyone else is looking for.