Any is too many, and I condemn lying.If you think of using an IFA have a read of the December issue of Which.
The report is grim reading A very high percentage of the IFA's investigated in the report were found to be lying about their industry qualifications.
On that note, as an ex-IFA (legitimately fully retired), while my qualifications were on my letterhead and website, I chose not to have them on my business cards. This was because in my experience my clients, who were mainly 'professional' people themselves, weren't too bothered, it was the relationship and results that mattered. After all, who checks in detail the qualifications of their accountant, lawyer or doctor?
If you are worried, check the name - both company and individual - on the FCA register. To have the correct FCA permissions, proof of qualifications and ongoing professional development has to be submitted to FCA. Although I am retired, my name still appears on the register, but as 'Inactive'.
Apologies for the heavy answer.
Malcolm