Your buyers are on the internet. They want chat - you can reply anywhere you can text.
Paste your link into your ad. Your buyers can reach you in meetings. Text them back & your replies go right back to them on the internet.
You paste your link into your classified ad on CL or wherever you sell. Buyers click the link and 'chat' with your cellphone over text messaging. Your text message replies magically go back to your users in the 'chat' window on the web. Your phone number stays protected.