SAYER, Barnet, early 19th century
Nigel Cross of Surbiton says: One of my forebears was a William Sayer born approx 1815 who was a tailor, perhaps from around Barnet but not sure. His father was a William Sayor [sic] also, but was a saddler, he died before 1846. Not much to go on..
As you failed to explain why you think there is a connection with Barnet, or include any source information, the amount of information I can provide is obviously limited. (See the instructions for Ask Chris and the appropriate help files on this site.)
However I can say that the only saddlers listed in the 1839 Pigot's Directory for Hertfordshire under Chipping Barnet (and nearby places in Middlesex) are James Butt at Whetstone, Charles Grout at High Street, Barnet, and John Sharp of High Street, Hadley. None of the listed tailors is called Sayer/Sayor.
Barnet is not listed in the 1823 Pigot's Directory for Hertfordshire - but may well come under Middlesex. There are no Sayers under Barnet in the 1845 or 1850 Post Office Directories for Hertfordshire.
These negative results may well be because your William Sayers were employees rather than principals trading in their own name.
If you can add to the information given above tell me.