It's hard to say. Some of the vendors travel around to other flea markets, especially when large one off markets are going on. Weather also affects things, bad weather less people so fewer vendors. That said, it's still the best flea market around and this is the best time of the year to go. Sorry for the vague answer.
Yes every Sunday
Yes, it doesn't look very crowded now
There should be quite a few today. No rain till later in the afternoon,
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