[Diolla]

If you have too much available credit it can hurt you when trying to get a mortgage but as you said you already heve the house.

Closing a card you haven't had long and don't plan to use will not hurt your credit score. If you were carrying debt and you close cards it can damage your score by lowering your "debt ratio" (how much you owe vs how much is available) but that doesn't seem to affect you either since you aren't carrying a balance.

It really sounds to me like as far as credit score goes it is a wash.

However, every time you apply for credit you generate a Hard Inquiry on your report and too many of those can lower your credit score so I would avoid opening one unless you really feel it is worth it.

That said... having alot of open accounts you don't use could make you a higher risk for identity theft. If it was me I would close newer accounts I didn't plan to use and keep open the accounts you have had the longest. Store cards are not really as good for building credit as the majors like Visa, Mastercard etc are.