One lesson here is to not associate the number you see at Credit Karma with your actual FICO score(s). The number there is not helpful to you, so stop worrying about it.
Here is another lesson:
On May 1, 2019 my Transunion FICO08 score was 578. On July 23 it was 662.
On May 1, 2019 my Equifax FICO08 score was 579. On July 23 it was 670.
In two months, substantial changes can be made. But what it requires is not new credit cards or new credit lines. It requires settling deliquencies and derogitories. Removing negatives, or getting them to stop updating each month. And then, it requires TIME.
On May 1, 2018 my Experian FICO08 score was 573. On July 23 it was 631.
I point this out to illustrate something: The Experian score is recovering, but at a slower rate than the other two because for some reason, Experian took a couple months longer to stop updating one of the settled delinquent accounts. The biggest, most important thing about repairing credit is resolving outstanding negatives so that they no longer update or better yet no longer exist.
Hang in there - you have the tools and the will. Progress is incremental, with a few larger jumps thrown in to make it exciting. Please invest your effort in to addressign those medical collections using the guidance above. It really will help. Perhaps a new thread specific to dealing with that collection is in order. Describe exactly what you see on your credit reports related to the collection.
It is wonderful that you are tackling this head on, and taking control. We can then revisit the Capital One question later at a time more favorable to your success!
