That's a decent price if the tranny is really well built. (I'm not knocking his abilities, but I don't know him so can't say.) I know that I paid $500 for my ZF5 and then another $1000 for a professional rebuild. But then, I assume, there's shipping on top of that and a ZF is pretty big. So it isn't a steal but isn't bad either.
Gary, AKA "Gary fellow":
Profile
Dad's: '81 F150 Ranger XLT 4x4: Down for restomod: Full-roller "stroked 351M" w/Trick Flow heads & intake, EEC-V SEFI/E4OD/3.50 gears w/Kevlar clutches
Blue: 2015 F150 Platinum 4x4 SuperCrew wearing Blue Jeans & sporting a 3.5L EB & Max Tow
Big Blue: 1985 F250HD 4x4: 460/ZF5/3.55's, D60 w/Ox locker & 10.25 Sterling/Trutrac, Blue Top & Borgeson, & EEC-V MAF/SEFI