400 bucks is a fair price in my opinion, and most shops guarantee their work. (Unless you have your own shop with a lift and all of the necessary tools of course.) It's not the kind of job that lends itself to laying on you back in your garage or driveway. Believe me, you'll have a cussing fit trying to get those transfercase skid plate bolts off if they've never been off before. And if that doesn't bug you, you'll have fun bench pressing the tranny... unless, again, you have the right shop equipment! You get the picture?
1951 CJ3A Universal: "Garage Queen"
1983 CJ8 Scrambler: "Project"
1993 YJ Wrangler: "Wheeler"
2008 JK Rubicon "Locked & Loaded"