How do you get rid of unwanted business?

When I interviewed one founder, he mentioned a few sites where you can sell your business, such as:

• Acquire

• BizBuySell

• Flippa

• GetAcquired

• Reddit (yeah, this one too)

Do you know more sites?

The question also is: Do you always sell your unwanted biz?

(I could see many people abandon it, sell it to a friend or pass it to a family member.)