What is the best way to settle my debt with CA and for how much?

You can give them a call and find out what they are willing to accept to settle the account. If these accounts have gone to collections recently, then the settlement that they will offer you may not be significantly different than the total amount that they are trying to collect from you. However, if they have been chasing you for a very long time then they may offer you to pay as little as 1/3rd of the amount due to settle the account. But as far as I know, it is not in your best interest to keep unpaid collections on your history for very long. Alternatively, you can tell them what is it that you can pay and see if it is acceptable to them. Just make sure that you ask them to send you a settlement offer in writing and you will pay the agreed settlement amount only after you receive the offer in writing. Also, ask them to send you a payment confirmation as well.