I'm building a Tempest Ranger trapmonkey. 18 rng/1 rog/1 fig.

I'm using a build I found on the forums, but as I'm leveling her I'm discovering the build is broken. Stats and Feats are not optimal. As I rebuild the character, I've discovered that I don't know what the ideal value for INT I should use. I'm fairly certain 18 INT is too much.

So, any feedback as to what value of starting INT I should use to be a successful trapmonkey? Then, do I up the INT or Dex stat for recommend value while leveling?