I thought I had three business days, or 72 hours, to cancel any type of purchase or contract agreement in New York State. Is this true?

 No. New York State does not have a general cooling off law for contract agreements. However, there are state laws that allow consumers an opportunity to cancel certain types of written contracts. Examples of these contracts include, but are not limited to, door-to-door solicitations, dating services, health club contracts, campground contracts, and home improvement contracts. The federal 'Truth in Lending Act' lets consumers cancel home improvement loans, second mortgages, and other loans where consumers pledge their home as collateral.

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CPB's Consumer Law Help Manual
For a complete list of the types of contracts afforded a 3 day “cooling off” period in New York State and other laws that may apply, click Contracts at the Consumer Law Help manual for more specific information or call below.
URL: http://www.nysconsumer.gov/clhm.htm
Contact: Consumer Help Line
E-mail:webmaster@consumer.state.ny.us
Phone: 1-800-697-1220