3 Blogs with duplicate content

I have 3 blogs, each one targeting a specific geographic location (real estate),
however all 3 blogs pretty much have the same articles with just the city names changed.
Is this bad ? anything I should do or look out for to improve my rankings ?

It is not bad at all. Some people might have different opinions about this.

I have few websites that have 100% copied contents but rank well on Search engine and more than 80% traffics are from Search Engine.

So, duplicate contents are bad? Some people might say yes, some may say NO.

But if you can write original and unique contents, that would be the best!

Better you create different content for your websites..!

dupe content works fine. i have 6 blogs on the same front pages for many search phrases and they all have the exact same content.