Sometimes you just can't win. There's a free app called Auction Sieve that can help with things like this. It has its own limitations but you might want to take a look at it.
What it all boils down to is how much time do you have to spend searching eBay every day? When I was actively buying old Xmas lights years ago I went through pages of new listings every day. There was no point in setting up searches as many sellers were either idiots or deliberately gaming the system by putting stuff made in the '60s or even the '70s in the pre-war sub-category.
I'm sure I really POd a number of collectors back then because I routinely paid fifty cents to a dollar over the market price for bubble lights. Royals were going for $4 so I bid $4.50. And now, 15~20 years later, they're going for over $10 apiece. I wasn't the clueless noob they probably assumed I was—I knew exactly what I was doing. I have no regrets.