TZ- I hear you on buying blind. But, the most you can do is visually inspect the record, unless you want it play tested on a Fisher Price! I try to have a dialogue with Internet sellers- it not only establishes their bona fides, but gives me a sense of how much they know, and how critical they are. I’ve gotten records that were very conservatively graded at VG+ that really are minty and some allegedly mint/unplayed which had off center spindle holes, scuffs from handling, etc.
I’m not going to bother returning a ’bin cheapy’ that I buy for 6 or 8 bucks and get by media mail from a seller in the States. But, I’d say my ’success rate’ for good players is probably in the neighborhood of 80% of what I buy. Some vendors, like EIL, sell absolutely impeccable product (unless they have noted otherwise in their description), but at a price. Others- well, I’ll tap into a vein- someone selling off a collection and I may find several juicy morsels from them before that well runs dry. Shipping costs between countries are now getting too high for ’average’ records- I wanted a Queen UK press of News of the World, a pretty common record in the UK- postage was more than the cost of the record.
Pre-Internet, I used to carry dog-eared lists with me on virtually all my travels, business and pleasure.
The one thing I’ve found to be true for shows and bin diving- sticking strictly to your "list" will often blind you to some really good records that are probably worth purchasing. But, that requires effort. And, I’m lazy- I just want to go in, see the booth marked-- "here’s the stuff you want", buy it and get out of there. I have friends that can spend days at these shows pouring over crates. Those are the guys who score at shows. (Oh, have you ever been to a record show with decent food?)