I'm suing a nursing home for disregard that made my father get his leg cut away. The lawyer needs to charge 45% in addition to I pay for every one of the costs they cause during the case. This appears to be very an excessive amount to me. Is this a normal rate?

I'm suing a nursing home for disregard that made my father get his leg cut away. The lawyer needs to charge 45% in addition to I pay for every one of the costs they cause during the case. This appears to be very an excessive amount to me. Is this a normal rate?