As someone who knows very little about the internet ad business in general this sounds interesting. Would you mind sharing how you do this in abstract terms? Do you just enter the site and check the "Advertising" section or is there more to it?
I use the chrome extension and when im on the site i can open a drop down menu with everything running on the site. I look for tag managers, ad exchanges, retargeting tags, data reseller tags, ad tech tags, etc... With one glance i can usually tell how sophisticated of a media buyer they are and if they seem eager to experiment with new ad offerings. (i.e. lots of small and obscure ad services or expensive data+programmatic exchanges like chango, etc...)
Unsure whether you're saying that you're a paying customer or not, but if so do you see a value above what something like Ghostery or Wappalyzer can tell you for free?
not a paying customer. Haven't tried those other tools.