After removing Low Search Volume KWs, I was left with 270KWs. May I try Location based KWs?

We don't recommend that. It isn't going to get you more volume on a local campaign. It is more narrow of a target. 270 KWs is a good start after low search volume. GO back, read the response to your KW review request and use the information. New KW ideas, urgent, high buyer intent KWs, etc. This is what drives the volume. Also consider your bids may be too low to drive high volume out of the gate. We teach you to bring things up on a slow control pace so that you can find all the low hanging fruit along the way. If cost isn't an issue, then by all means, raise your bids and your volume will increase (if there are calls to be had).