G.T.A. Querry

It comes under RCM basis.

Tax is to be paid by recipient.

5% with no ITC or 12% with ITC based on conditions

If firm is registered under GST as you said in that case firm have an option either to charge tax @ 5% without ITC or 12% with ITC. Else they also have an option to not charge tax in that case company needs to pay tax under RCM @ 5% and can claim ITC.

However, the GTA has to opt at the beginning of financial year. *As per Notification No. 20/2017-Central Tax (Rate) 22nd August, 2017

Agree with Sourav ji

Agree with Abhay ji

Depends on what option you have chosen. If rcm then 5% will be paid by your client and you will not be eligible for any itc.
if forward charge then 12% will be paid by you. you will also be eligible for itc.
once opted under forward charge then cannot switch to rcm route.
For further query you can mail me