To be able test any implementation of Android Market licensing (e.g. LVL, In-app Billing), Google advises to create a Google Checkout test account, since the developer cannot buy from himself using his own Google Checkout account.
Sounds great except that the test account must use a real credit card.
Which begs the question: How is this different from a normal account? What is the advantage of a test account over a normal account?
On
The test account does not have to be associated with the google checkout account. The publisher can have his/her google checkout account set up against the android market account. And as a developer, you can have a test account created. Test account holders can test the application for LVL and in-app purchasing, etc only if the application is uploaded on the developer console. It does not have to published. But it has to uploaded and activated and saved. So, it's not true that the test account holder has to have his/her financial details registered with the Google servers. Only the publisher has to do that. And the publisher can add as many test account holders as he/she desires. The publisher will provide a publishing key and that's all the developers need to implement/test their code.
Look for documentation on Google developer site. It explains well.
HTH.
You don't need a separate test account. That's only if you want to include others as testers. Your own publisher account is just fine. If you set the LVL response in your developer account to, say "UNLICENSED" for testing purposes, then only the devices that are set up with that Google account will get this test response.