building at 310 West 55th Street

I'm wondering the same thing - did you find anything out?

One explanation could be the large width (taxable surface area) of the building coupled with the (relatively) small number of units/shareholders (62). The other explanation could be poor financing of the building.

At an open house year+ ago the broker said the bldg had a lot of deferred maintenance costs after years of pensioner control. But of course he added "everything was better now".

Relatively small number of units and full time doorman. The current listing says condo, but it's a Coop building?

The current listing shows $1.5 per sq ft which is very low for a coop with doorman. Normal maintenance for doorman coops is $2 per sq ft now. Condos even higher including taxes. Previous listings, which are higher floor, are $2 per sq ft. What do people think is normal?