What should I expect to pay to get this done? I looked up at what is normally recommended when changing these (gasket, pigtails, harness etc) and looks like $250+ in parts before any labor is done.

Here's the deal, guy offered me his '02 Ford F250 ext cab with a 7.3L PS for $8500 but he said the valve cover gaskets need to be changed. Trying to decide if this is a good deal.

Did you shop the parts separately? A quick look online shows some kits for considerably cheaper that includes all the parts.

I'm not a diesel guy, I never knew valve cover gaskets could get so involved.

https://www.amazon.com/BLACKHORSE-RACING-Gaskets-Powerstroke-1999-2003-F81Z-6584-AA/dp/B07DWX48MY/ref=asc_df_B07DWX48MY/?tag=hyprod-20&linkCode=df0&hvadid=316634728555&hvpos=1o3&hvnetw=g&hvrand=9536831579636037103&hvpone=&hvptwo=&hvqmt=&hvdev=m&hvdvcmdl=&hvlocint=&hvlocphy=9027906&hvtargid=pla-494326086158&psc=1

The job is relatively easy. The parts can be found for less but you have to expect to pay for markup. I guy has eat.

I bought my gaskets and under cover glow plug harnesses from riff raff diesel (riffraffdiesel.com). Very happy with quality. Lately I have had some concern with counterfeit parts and buying there gives me some peace of mind. I have emailed with the owner and he has always anwsered quickly. Its my go to place now. I changed my glow plugs, harnesses, gaskets in two afternoons. I also Re-torqued the injector hold down bolts and rocker arm pedestals. I have instructions and a tool list some where. The odd things are a woble socket for the back valve cover bolts and a piece of 1/4 vacuum hose (used to insert/remove loose plugs). I did not change the pigtails on the outside of the valve covers, just plugged it back in. Truck has never started better.

This is a super easy DIY.

It would be nice to know if the antifreeze was maintained properly or switched to a diesel antifreeze. The regular can cause cavitation damage if not maintained, additive used. I flushed and changed to the red ELS for diesel engines a while back so I didn't have to worry about additives. Someone on here also suggested starting it cold, sitting overnight, no block heater.

White bear auto nation will have the cheapest parts and be OEM. Price them there. If all you have wrong with an old 7.3 is leaking gaskets, then I'd have no problem taking that truck. DIY the repair.

Thanks everyone! I'm always worried about messing it up when I attempt a DIY project - especially since I grew up with gas trucks not diesel.
I appreciate the places y'all have recommended to buy parts too. Definitely helps!