Automation test for SOAP services?

in our architecture we have mule application with a list of webservices, we use jenkins for continuos integration/deployment. No automation test at all at the moment, only few unit tests.

I was thinking to add a step after each deploy to test all webservices, something like:

• input: url and request body
• output: check the response code, than the response body

my questions are:

1. Should I use a framework to integrate in our code?
2. Is a simple file with the list of the webservices and a file for each response/request a good idea to do that?
3. which tool do you advise me?soapui?Can I do everything I need with the free version one?
4. should the test be ran after each deploy?

Any advise or thoughts on that?

Thanks