It's worth about $13,000. See quotes at http://www.edmunds.com/gmc/sierra2500hd/2006/index.html
The 2013 GMC Savana is 18 ft. 8.1 in. (224.1 in.) long.
The 2013 GMC Yukon is 16 ft. 10 in. (202 in.) long.
The 2013 GMC Terrain is 15 ft. 5.3 in. (185.3 in.) long.
The 2013 GMC Acadia is 16 ft. 8.8 in. (200.8 in.) long.
The 2013 GMC Yukon-Hybrid is 16 ft. 10 in. (202 in.) long.
The 2013 GMC Sierra-3500HD is 18 ft. 9 in. (225 in.) long.
The 2013 GMC Yukon-XL is 18 ft. 6.4 in. (222.4 in.) long.
The 2013 GMC Savana-Cargo is 18 ft. 8.1 in. (224.1 in.) long.
The 2013 GMC Sierra-1500 is 17 ft. 1.6 in. (205.6 in.) long.
The 2013 GMC Sierra-1500-Hybrid is 19 ft. 1.9 in. (229.9 in.) long.
The 2013 GMC Savana has a 6 yr./ 100000 mi. warranty against rust.