What’s the etiquette?

[Mike Alber]

I found a multi family house on a broker's site... but then, in researching, found it listed (more cheaply) on Zillow as FSBO. Any idea what the etiquette is here? I've emailed with the broker a couple of times now. Should I keep talking with the broker but try to get the cheaper price? Or go straight to the owner through Zillow and cut off contact with the broker? This feels like kind of an odd situation but maybe it's more common than I think?

Im very green and could use all the advice you’ve got.