2008 f150 I suspected that my pcm was faulty so i sent it off to have it refurbished.It was a plug&play deal.Several weeks later company notified me to say it was beyond repair.I need advice on the cheapest route to replacing pcm and what to do about the chip in key?

 

The cheapest route is to buy a used PCM from a U-Pull junk yard but you need to know exactly what you are looking for. They cost $37.99 at my local U-Pull yard in Mobile Alabama. I would call your refurbishment company and ask for advice on what exactly you need to buy, I do not know.
As a minimum you are going to need your VIN number.

 

Quick Google search shows these guys.

https://www.fs1inc.com/ford-pcm-ecm-...9&p=5&year=124

Never used them, but prices look good.

You'll likely have to get some stuff programmed, at least a key. Fobs are easy.