abnormally high maintenance but great location

Unless you give us specific details to examine, we can't substantively comment. Cough up the link for the listing.

landlease?

Anyway, if 10%of the units are up for sale, you'll hardly be divulging a secret by posting the address here so that others can analyze for you.

I've been looking at listings for a particular east side coop. (giving up on UWS listings?)? only one of several brokers has written into the listing that the apt is in a land lease building. Are brokers legally mandated to reveal this? Should I have to email each broker on any listing that seems to be too attractive?

Sounds like the building is land lease. If it is, getting a mortage could be veru difficult depending on how many years is left on the lease. It is not uncommon for lots of apts. in a singe land lease building to hit the market at once if the klease is nearing expiration.