How many breather hose valve covers are there

It all depends on whether the sytem is an open or closed PCV sytem on your car. I have included a diagram to show the difference. A Positive Crankcase Ventilation valve is part of the thing that got fixed. The PCV is in the valve cover and connects to a hose which goes to the intake manifold. If it is open, then the other valve cover will simply have a breather. The picture is from an AUDI manual, but it does not show that some systems will still have a hose from the other valve cover to the open air breather.
A closed sytem is the same on the PCV side. The other valve cover will have a Closed Crankcase Ventilation valve, CCV, as shown in diagram which goes from the CCV on the valve cover and connects it to the throttle body.
How to know exactly how your sytem for your engine should be set up. Law requires that an under hood emissions sticker be put on all vehicles. I included a diagram of the information they have on them. To the right you will se a diagram which shows the Crankcase Ventilation Sytem. In the case of this example, it is closed becasue it has a CCV on the one valve cover and not an open air breather. You will have this sticker under your hood. It will show what ype and how the hoses are routed for the engine in the vehicle. If it shows a Closed sytem, you may have been charged properly. If it shows an open system I would ask for an explanation. The reason I say you, "may have been charged correctly" is that the part number is duplicated and most systems are not symetrical and you will be able to get an idea of this from your underhood sticker. There should be only one hose to the intake and one hose to the valve cover. You will have to see if your sytem has two of each or not.
I would still like you to look at the valve covers and find two hoses that run from the valve cover(s) to the intake manifold. Or, I would go to the mechanich after looking at the underhood sticker and ask him to show you the two identical hoses in both locations. It sounds a little fishy to me, but not impossible.
So, just tell the mechanich you, "were confused about the sytem after looking at the underhood sticker and wnated to make sure it was in compliance for emissions issues".
That way you can ask him to show and explain to you the new hoses, which should look new, and their correlation with the sticker and you will not be approaching him by accusing him of anything. He may have made a mistake and once you do this if he made a mistake or sees that you caught him, he should refund your money or show you where the parts are.
Plus, you will be educated a bit to understand what you are looking for and what he will be showing you.