Here's an '05 Suburban for $7,250. https://frederick.craigslist.org/cto/6001662666.html Looks like a Z-71.
Looks like he started at $7,950 and has lowered it to $7,250. Private party "Good" is $5,415. "Very Good" is $6,012. Call him up with that info, offer $5,500, and see what he says.
This...