They can flag your credit history as "fraud victim" and nobody will be able to get credit with that identity without providing extra information.Jon

However why is it a red flag for the buyer to ask you to send them an email?

BUT, if there are other red flags on credit report -- such as a multitude of collections, high debt, history of late payments, etc. then absolutely not.

But if they say it isnt since it was just an addition I can agree that it raises a red flag with proper permits when it was built.You are correct that they may consider it "new" since it was rebuilt but the city may view it as a remodel.  

Ive been flagging these types of ads whenever I see them.

Tag a name with the @ symbol and it will flag us for the response. 

Waiting for it to hit the market sucks because then it has an investor red flag for 7 days and you can't put an offer in until it's off.

I pay for gas heat at one of my 4-unit properties, and I can live with that because I can control the thermostat, but ceding control of electric would be a red flag for me.

Any red flags here?

They have high initial yields and some see that as the red flag.