well, the problem is , that many people want authentic tea for common price. That leads vendors to sell 10$ tea with 100$ story
speak of pu-erh tea:
Location is important not only for vendors but also for drinkers. Each area has it's taste specifics and there is a big difference between Bulang or Yiwu for example.
Should tea be called A and B , you would have to stick to 1 vendor for good, since other vendor might use the names other way around
I believe that it's about the cases like LBZ for 10$ incl. shipping. In that case is clear , but some comparing prices could be harder if difference is not that radical.
Comparing prices : it is doable with big factory produced teas , yet, the researcher would have to take in account the vendor's expenses. Means know why vendor A sell 100$ cake and why vendor B only 60$ very same cake. The answer might not be the " fake " , but that vendor A has workers, shop in big expensive city or mortgage to pay .....and so on. Those things are not easy to research , especially online shop . It is big difference of m2 rent in Kunming and in Shenzhen, HK or NY with London for example. Not mentioning the salaries. So vendor's location can be a slight guideline.
Speak of non factory / branded teas, it get much more complicated. Many factors are involved in final price along with those mentioned above. Unless you know the price of fresh tea leafs specifically for that tea in that area ( place , garden ) particular season, amount which was purchased by vendor / producer and sold by particular farmer ( same place different farmers also have different prices, also same farmer with different buyers have different prices ...depends on you cooperation concept with farmer ) . So easy said, u'll never get it right.
Things get more complicated when "free shipping " is involved. You would have to research how much the actual shipping fee cots from the sender's place. Some vendors might have postal contract with better prices. So only way is to check the similar similar item ( like 357g cake ) which is not set with free shipping form the same vendor and see the actual shipping fee.
I don't see in reality normal person spending hours of researching anything of that. Just simply go on some forum like this one, ask question about tea vendor, will get forwarded to first 2-5 big names and that's about it
Anyway, nice article. Good job.