I want to find out what the current owner paid for an apartment (in Manhattan) I am interested in. It was purchased in 2001, and I can't find any sales information here or on ACRIS.

Is there any city office I can physically go to and get the information?

if it's a coop sale in 2001 I don't think there will be any information available. If it's a condo or a building the info would have to be on acris or it would represent a recording error. Condo, coop or building???
2 dollars say's it's a coop.

its a co-op.
where to send $2 :)

A neighborhood-based listing broker might remember having sold it in 2001.

what difference will it make knowing what he paid in 2001? I'm sure its a lot less than what he is selling for..

you could ask the managing agent for a historical list of sales, or you could ask the owner.

A little creativity sometimes may get you the answer.
Check all the 2001 filings for 2001 in the building on Acris and read each page.
You may find how much tax was paid on the purchase and reverse calculate the purchase price. I know for sure you can do this with some condo purchases of that time but not sure about co-ops.

Nope, doesn't work for pre-2003 co-op sales. The tax (if there was any back then) wasn't recorded. Once in a while a loan amount will be scribbled on a UCC1 form, so you can guess at the sale price if you know how much financing was allowed back then.

It does work for old condo sales, where you divide one of the taxes by .004.

There's a slight chance the co-op sale was reported in the NYT. Those don't give an apartment number, but you can check the UCC1s for several weeks ahead of the newspaper's date to get that.

Identify the address and unit, and I will see if it is in our firm data-base.

Back in the bad old days, brokerage firms saw a competitive advantage in exclusively having (and keeping close) past sales data. Agents at firms with management companies could access complete sales data in company-managed coops and condos, while agents in huge firms (like mine) entered sales data for sales they were involved in (including on the buyer side). Our data is by no means complete, but it is extensive.

I maintain my own data-base of downtown loft transactions going back to Nov 2008, and I add past sales for those lofts when I can find it; there are many that go back to the 1990s. Worst case, I am likely to be able to identify who the listing agent was.

I readily defer to sensei NWT, our resident ACRIS guru.