is contracts&tax&banking necessary for even testing IAP?

I have been struggling to test the IAP response but it is returning empty. I am now in the very beginning of one app, and I don't want to submit the contacts and banking and tax stuff that early. are these necessary for even testing IAP results locally? I think it does not make sense if I have to.

is contracts&tax&banking necessary for even testing IAP?
 
 
Q