GTA And ITC

we are registered GTA service provider having 20 Truck. we make our sales bill without Changing GST. clients paid GST on our behalf RCM basis. now question is should we take ITC on our expenses like Audit Fees, repair in our own truck. insurance premium. telephone expenses etc office expenses. now office management deside to charge GST @ 12% on our sales Invoice and take ItC. sir it is possible? please answer my question