Im a small time, new seller to ebay,  not familiar with this PeSA thing,  but in regards to what you can learn from paid courses,  you can actually learn quite alot... if you want too.    

 My inlaws paid waaaay too much for a course from the states about selling on Ebay,  especially since the course didnt touch on  Ebay.au at all and selling in Australia is slightly different.  Anyway passed the course to me so I did it.    I still have some videos to watch but I actually learned quite a bit that I would not have learned from these boards unless i knew the right questions to ask,  which a beginner would not.   For instance there are actually plenty of ways to market yourself off of Ebay but by using Ebay so you can really grow your business.    

So moral of my post is if you are paying up to 1000 maybe 1500 bux and you want to really grow your business these courses can be really helpful both from learning new things and from taking inspiration and motivation from the people around you.        My inlaws however paid 10000  😞      hehe and thats a ripoff!