Can a 3rd party collection agency go into your checking account and take your money?

I live in Pennsylvania and the amount is 400 bucks

No.

They would have to take you to court, and you would have to defy the court order to pay them in order for them to get your money from your checking without your permission.

If they have a court order allowing them to attach your bank accounts than yes. This would require them getting a judicial order. However, this could potentially happen before you have gone to court to contest the matter (it is essentially a preliminary injunction "freezing" your assets to ensure that there is enough to satisfy the judgment). Absent a court order that authorizes the other party to get a preliminary injunction or a prejudgment attachment, than no, they cannot do this.

unless you actually give them your account information, they have only a slight chance of knowing what institution you bank with.. besides that, most 3rd party agencies won't bother with the court costs and attorney fees it takes to get a judgement/garnishment on a $400 account.. at $400, i assure you, it's not worth them sueing you over, but they'll pull the hell out of your credit bureau report!! it's best for you to just pay it and raise your score as quickly as possible

No. Only if you give permission for them to take money out of your account. They can drive you crazy by calling and sending you letters but unless the original creditor takes you to court and gets a judgment, tell the 3rd party to back off and not call you.

Not without a court order.

Did they take 400 or do you owe 400?

If they took money out of your account, they might have impersonated you at the bank, which would be a felony.

You might get to sue the collector.

I don't believe so. However, you should pay your debts or risk a bad credit report...