I make signs full time ..... I have a CAMaster CNC, a decent set of German chisels, lots of chisel writers ( lettering brushes), a new plotter & an old one I use for cutting sandmask. I'm in a very rural area in Canada, but I have about 130 million people within an easy day's drive. I specialize in dimensional signs .... about 50% of which are residential, since there are a lot of "summer" homes on the lakes around here.
I've been doing this full time for over 20 years & we all struggle with pricing..... mine has been fine-tuned over the years.
So, I have a base charge, plus an amount per square foot. Depending on the intricacy of the artwork, both the base & the sq.' can change. Other "value added" options, like gold leaf, carved appliques, etc., are added on as well. You have to think of it like your buying a new vehicle .... you have your base price, plus the packages, plus the extra options.
Design time has to be factored in there too .... and that's a difficult one anymore, since so many people have rudimentary design programs at home . Most don't give any value to the design, which is, by FAR, the most important part of any sign. A poorly designed sign is both ugly & useless, no matter how fancy your carving is .... but a well designed sign will look good painted, printed or carved, on any substrate.
The hardest thing anymore is getting a "design" deposit ....people won't open their wallets until they actually see their "name " on the design. So, you just have to build "unsold" designs into your overall pricing. I don't much like it, but that's the way it is here in the 21st century.
IF you only want to do multiples of the same design, prepare to carry an inventory & prepare to sell cheap.
IF you're willing to do "custom" work, your inventory will be materials you need in stock, cutoffs, paints, etc...
If you don't want to compete against everyone else "fighting for the bottom", you'll need to offer a warranty.
I don't want to post my formulae here, but the average price for my dimensional signs is about $750 US. I'm posting a couple of pics ....
Keep in mind, "cheap" doesn't guarantee sales. There are people with money, who will always have money. During the last recession in North America, luxury car sales actually rose!