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If the bank/collection agency agreed to delete once paid in full, that will be your biggest jump in score right there. I would make that your highest priority for now.
I recently saw a collections account pop up on my report, i paid immediately, and they deleted it. I saw a 50 point jump in score in both directions when this occured from start to finish. This was only one tradeline, you have six (?). I would think it would be a most significant jump in score for you.