The sheng puerh is a little different from green tea in processing. I'm sure you can google it , so I'm not going to write more about it.
Speak of the judging quality, is long journey for everyone. Many beginners tend to judge a puerh tea by the actual
taste of the liquid
only. Searching for some notes reminding fruits, flowers ..etc.
Long time puerh drinkers consider another factors, like the thickness , mineral richness and overall body feel after drinking, in Chinese called "ti gan" - body feel. Very discussed topic " Cha Qi " - energy of tea. ...lots of arguments / discussions / opinions about this are on Reddit
https://www.reddit.com/r/puer/comments/ ... nd_cha_qi/
https://www.reddit.com/r/puer/comments/ ... d_a_usual/
Aside of the true quality , there is also a marketing. So the prices are not entirely dependent on above mentioned factors. You will learn that by reading , trying , purchasing tea. So don't be surprised that low quality tea from village A is 5x more expensive than some very good old tree material from village B . Chinese sometimes pay high price for village A, because it's famous and they just want to show off have money to buy that one or give a "mian zi" ..face. (cn thing though).
Read some blogs, lots about on internet. Buy samples from beginning, if like something, buy full cake / brick. Store it and come back to it few years later. It is very educational concept.
Don't just search cheap tea for storage just because you don't want to invest more money to something you don't understand yet. Low quality sheng is not worth storing ( taking up the space in your room ), unless you do some investor business buying a ton of it and store for 10+ years or something

...like buying some TF brand like Dayi and wait when they lift up the prices and you are able to find buyer. ..different concept though.
Think of it as bottle of wine you store / hide / save for some special moment. It's not going to be some 5$ fake Bordeaux in cardboard box , right?
Don't be afraid to ask questions on dedicated forums , but do not take all answers as 100% true. Many things are depended on experience / knowledge , which you hardly can confirm from individuals posting on internet. Like me , you do not know who I am, so take my advice just as another piece of puzzle which will forms out in time when you read more posts from other places and other people. You will slowly learn what makes sense and what not.
It does take time, so your best friend is the
patience !
have fun
