The RP (Responsible Pharmacist) cert has replaced the old Reg Cert required to be displayed in the pharmacy. Legally that is all you need. MUR certs, Smoking Cessation, etc all are extras. MUR cert will cost you, but unlikely to gain you any more money.
Some employers insist on one before offering a locum. However, they will not close the pharmacy and refuse to employ you if you do not have one. Local PCT will advise---if still there!.
johnep