The Importance of being upfront with any problems.
We don’t like it & often it’s not our intention.
If that ‘stuff’ impacts your credit file its very important to be upfront about it, lenders appreciate that, and they will find out so tell us. If you’re honest and you give all the mitigating reasons, and show what you’ve done since then you may still not get the new loan want but you have a much better chance than if you don’t, and you aren’t wasting your time. This also gives us the opportunity to workshop it with lenders and see who’s most likely to approve you, which protects your credit history.
What is absolutely critical is that you show good faith in dealing with credit hiccups - do not put your head in the sand. Lenders can see when the date of any listing, when your file was accessed after this, and when you got around to fixing it up. If you’ve ignored a default and they can see you knew about it looks bad. If they can see that promptly act as soon as you know about it, either paying the credit or disputing the bill (and documenting everything you do to dispute it), that’s better.