OK, as I prepare my credit, DTI, and savings for a multifamily purchase, I would like advice on my current car loan situation. This would obviously significantly lower my DTI ratio, however would temporarily lower my credit score as I used cash/credit to cover negative equity. However, it would also "free" up nearly $800 per month to pay down cards and replenish spent cash. I've overthought this so much that perhaps common sense has left me so ANY financial advice from those with more experience is greatly appreciated.

Here are the details:

Balance = $23k @ 5.9%, 2.5 years remaining
Payment w/ Insurance = $765
Negative Equity = $7k (increased from 3k to 7k after new year)

Paying the negative equity would max out 2 cards; 1 is 0% APR and the other is 15%. Not having this mode of transportation is not an issue. Again, thank you for any advice.