. . . still keep decent credit rating?
Agree with all the others. It may not necessarily seem intuitive what is "good" or "bad" for a credit score. For example, I just checked mine and, while I have no need to worry about my score, the areas I could "improve" are
*"
Lack of recent installment loan payments:
Your credit report shows no recent non-mortgage loans (such as auto or student loans) or sufficient recent information about your loans.
Having a loan along with other types of credit demonstrates that you are able to manage a variety of credit types."
*"
Too few accounts currently paid as agreed:
Your FICOŽ Score considers the number of accounts where you are paying your bills as agreed.
In your case this number is too low because you have very few accounts or because you've missed payments recently on some of your accounts." [I didn't miss payments. I have "too few" accounts]
Cancelling an old, established credit card (credit history counts!) or reducing your credit limit will negatively affect your credit score.
I don't feel as though one should live their life trying to maintain the highest credit score possible. Beyond a certain level it doesn't matter -- I doubt there are loans/rate difference between 800 nd 815 and 849. I'm not going to open more accounts or take out a car loan to "help my score". But I
have kept my oldest credit card, even though it has no rewards, just for the credit score boost. I suggest a quick Google to find out the ways credit scores are accessed. Don't be a slave to it, but no need to metaphorically shoot yourself in the foot.