Question about raising credit score...

Hello,

My husband and I are trying to improve his credit score. While I don't have his "real" credit scores, we have recently pulled his credit reports. I am going based on what Credit Karma tells him, which is a score of 598.

Positives: He has one auto loan that is 2 years old and has no late payments (will be paid off in August). He also has 3 credit cards, 2 have been open for about a year, one has been open for about 6 months. No late payments on those either.

Negatives: All 3 credit cards are almost maxed out. He has 3 accounts in collections which amount about $200.00. All three are scheduled to come off his credit report in Feb/March 2015. One is a lumber yard bill, one is a chiropractor bill, and the last is a hospital bill. I have contacted all 3 with pay-to-delete letters and they have all declined (saying it was illegal to do so, though I know it isn't).

I already know that paying off the credit card balances and keeping them low will raise his score, and we will be doing that this month.

My main question is about the collection items. We want to, and we can, pay these off this is not an issue. He does owe the money and we have it. My concern is that we have read that paying off collections will only hurt your score, and that you should instead wait until they have fallen off your reports and then pay them. Does that rule apply here since they still have 4 years left on his report?

Basically in his case, is it better for him to pay them now, or let them sit? Not only score wise, but also what looks better to creditors. For instance if we wanted to get a mortgage, rent an apartment, or get a new car loan.

Thank you in advance!