Conditionals

I've been studying the conditionals and I'm struggling a bit with れば and たら. I understand the grammar points but I don't quite get in what specific circumstances is each used (I do with と and なら), specially because a lot of times they are interchangeable. I was hoping somebody could maybe shed some light on it.

See the following thread.
たら vs. ば vs. と? Conditonals | Japan Forum