I get "ive got a plumber mate who'll do it for £x, can you beat his price" and I always say "good luck!" and walk off. I dont even try to compete, my price is my price.
It was the first domestic job I'd quoted on in a while having mainly done sub contract work lately, I may come round to your thinking Gall.
My pricing for domestic and commercial work are very different. My domestic prices arent expensive except when put them against a cheapo tiler.
Quoting for domestic work is more trouble than its worth.