You can ask your creditors to report your credit card's CL's to your credit, because if they are as you say, they would appear as they are maxed out and would hurt your credit card utilization... but once the CL's are reported, you should see an increase in the scores. A 3 month trade line isn't going to help a whole lot since it's just for a short period of time... the only time it would help is if there was no installment loans previously on your credit report, or if there was hardly any credit on your report either. Money market accounts are savings vehicles, not debt vehicles, and wouldn't report on your credit (at least mine do not, nor any of my clients who have money market accounts). If you want to raise your scores, then use the $4k to pay down/off your credit card balances.
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