I’ve bought some houses with 0% interest for a year credit card loans.

I seem to remember that I didn't even have a business card until then either.You are VERY late to the game to be making these decisions. 

They are business CC but I don't use them anymore and would rather use cash/debit cards.

Hold on to the cards forever (closing accounts or opening new cards can impact your score).

If you want a second opinion check credit karma, ask your credit card or your bank.

When you do it, you show your cards, but new people don't knew because they are thirsting for help and will take it from literally anybody.

With risks bring the higher chance the cards will collapse.

Did you pay with a credit card?  

A tax account ensures nothing is accidentally spent elsewhere, and a marketing account makes sure lead generation is always prioritized.From a credit perspective, connecting credit cards to these accounts on autopay helps you manage spending responsibly while playing the credit game.

But you play that card if you have to.