is it considered sale of business property, or sale of main home?
Sale of a main home if it was your primary residence for 2 out of the last 5 years leading up to the closing. You lived in it for 17 years so that shouldn't be a problem.
You can use the Section 121 exclusion ($250,000 or $500,000 if you're married filing jointly) but you do have a recapture situation if you rented this home or used it for business purposes.
The IRS generally has a 5-year period for conversion to personal use that they look at but you've more than satisfied that requirement.
