Short anecdote. I have been juggling around 10k of credit card debt between interest free (promotion) credit cards for the last ~8 years. I have way more than enough to pay off the whole bill at once so I'm not in danger of being in dangerous debt (spare me the dad advice, I know it's a risk, but I'm playing my odds smartly, I wouldn't do it otherwise).

Set the minimum payment to autopay and watch my credit score hit almost perfect since then. This works because 1) 10k is only ~15% of my total credit utilization so it doesn't negatively impact my score enough to matter and 2) I have so many damn "interest free for 14 months" credit card offers coming daily that I'm going to do it until they run dry and then just pay the balance in full (probably pretty soon). This has afforded me a few things 1) near perfect credit score because of 8 years of consistent payments and 2) because I'm a risk taker, the adrenaline and feeling knowing I'm playing the system a bit. 3) decent amount of CC rewards/cash back.

Proud to say that in those 8 years I've only paid interest once (forgetting to transfer before my balance before the promo period ends). I've also done 90% of the balance transfers for no fee by either promos or calling the CC company. They don't seem to be too reluctant to this because it benefits them to have my debt.

So all in all with fees and interest I paid around ~$500 over the last 8 years (~$60/year) to have a perfect Credit score. I'm at the point where I'm about out of these interest fee CC promo offers so within a few months I'm going to pay off the whole balance. It was a fun little adventure.

Disclaimer : I'm not recommending this to anyone I just wanted to share