On the subject of buying stuff for DIY (not breakfast), I can add:

In general I find the trade-orientated outlets painfully over-priced
and staffed by people who would not be allowed to work in B&Q, Wickes
or the like. Occasionally, and only occasionally, it is different.
These week I tried to buy a slightly unusual Honeywell actuator for a
valve on an underfloor system. I had the old one, so the part number
was clear and I had tested it away from the system to confirm that it
was caput. I e-mailed Honeywell and they gave me the names of the two
largest outlets - normally suppliers to the trade.

At major outlet number 1 (maybe the larger plumbing/heating group),
the man at the counter said he hadn't a clue, it wasn't on his system
and he wasn't sure. I suggested that he contacted Honeywell since
they had given me his Co's name. Grudgingly, he 'phoned and came back
with, "Yes, Honeywell has them, they're £24.40 inc. VAT".
"Please, order me one, I'm happy to pay in advance so that you know
that you won't be left with it", I replied.
"Oh, did I mention the £25 charge, 'cos we've got to order it", the
surly sod added.
My reply involved sex & travel

I 'phoned major outlet number 2, and asked again. "Don't see it on
our catalogue but give me a little while and I'll 'phone you back".
An hour later he did call back with the good news that he'd have in by
the next day. Price the same £24.40. When asked if he wanted payment
in advance he said no. When I collected it all I had to pay was the
price quoted. The intelligent employee even asked what it did and how
it worked so he'd know next time. When I told him about the other
outlet he laughed and said that he used to work for them and that it
went on all the time -- they just made prices up to rip-off non-trade
customers with special charges etc.

The second supplier is PTS part of BSS.
I will get all my special plumbing stuff from them in future. I'll
not name the other place but I'm sure lots of people know who they
are.
Naffer