I always get an image of a slightly curmudgeonly chap waving a clenched fist at a pesky kid any time Mike comments on "Euro Mod DJs" and the value of records.
When you have decades of experience in collecting a genre, of course you have superior knowledge and contacts which will generally improve availability of records and reduce costs. You'll have lots of dealer/collector friends who share you passion, know what you like/need and generally, your pursuit of records is going to be considerably different from a guy born in the 80's on another continent who only has access to most garage records via eBay/the Internet, compilation lps, club nights and podcasts or similar - of course the newbie is going to be more susceptible to what's in vogue but I don't think that makes their passion any less genuine.
I really value your knowledge Mike, I've really appreciated you input when I've asked on price advice when making some of my biggest purchases but I don't see why you get frustrated and are so dismissive of other collectors. At worst, they temporarily drive up prices on records you probably own or don't want and at best provide you with an opportunity to capitalise on their greeness/eagerness when something is flavour of the month.
Things like The Raven, Calamity Jane are a prime example. It's a fun tune but it's basically novelty pop. It doesn't appear hugely rare but appears on ebay fairly infrequently, a few times a year, so it was ripe for its value blowing up when it was brought to a wider audience. I remember seeing that in a shop in London for £500 at the peak of its popularity. Now, pretty much every month, there is a copy posted on Facebook with the price slowly decreasing, shifting it for £175 now seems a challenge and the last few copies on eBay are well below that. That situation is not uncommon but surely it gives guys with experience a chance to capitalise on the situation, or you can totally ignore the buzz and wait for 18 months for the market to readjust.
I saw the thread that brought about your initial post. Personally I thought it was an odd record to ask for offers on, first and foremost it's not hugely to my taste but it's one I've seen offered multiple times at relatively stable prices so wouldn't have thought it would be too difficult to price up, as he'd done with all the other records he offered. I doubt very much he sold it for £300 if he sold it at all but, if he did get a buyer in the region, so what?
For me, the most irritating thing about the Facebook groups is that you see the same records offered every week by the same sellers that are readily available elsewhere at a fraction of the price. I even got kicked off one of the pages for having the audacity to point out that the record offered for the 5th time in a fortnight at $40 was readily available on eBay and Gemm for $5 in considerable quantity.
I've found the Facebook pages quite fruitful, bargains can be found but more often than not, top dollar is asked there. I personally don't mind paying a slight premium for convenience and instant satisfaction. I've also made real life friends and met people all over the world thanks to that community so it's got additional value to me.
Record collecting really is a funny old game though.