Keep in mind there's no evidence other than in pharmaceutical company advertising there is any difference in the amount of any neurotransmitter in a depressed or anxious person and any other person. M4 is right, it's the symptoms you're suffering that determine whether you need treatment, and it's the severity of those symptoms and how much they're disrupting your life that determine whether you need medication or not. If you're trying to determine the best med to take, that's more a question of liver metabolites than amount of any neurotransmitter. If you want to get all these kinds of tests you have to find what's called a functional physician, a psychiatrist who actually practices medicine. They're expensive, there aren't many of them, they don't take insurance, but they will test you to determine if there's any physiological cause of your symptoms before determining whether medication and which medication is most appropriate.
If I would have an idea I wouldn't ask and concider to take the test.
Are urine dope tests effective? Yes. Same thing goes for neurotransmitter tests. Some people think neurotransmitters are only happening in the brain but they in all your body and so leave trace all over your body including the kidneys and a ratio will be completed with the result to give you a pretty accurate result.
The question is: do you really wanna pay 400$ to know that? Will it haves impact on deciding wether or not you will take medications? The choice is up to you but you can already have a good idea of what's going on with your neurotransmitters based on symptoms.
M4