In markets with high costs, the rate will be high, in small towns it'll be low. In general for 10 yeasr experience, it'd be right at the average income level for the graphics trades +-10%. If the person has additional skills that benefit the business they may skew higher. US data by county is at the link below, select the year, search Industry for sign manufacturing. If there is no labor reported the county will not show up.
QCEW Data Views
Payscales are directly related to the performance of existing businesses as a mathematical model in their market. Simply put - pay is based on what local sign businesses can afford, not what an employee wants to earn. Larger sign firms are usually more specialized (market niche) and efficient. That niche flows to the shop's labor needs. So these shops usually pay more, whereas a smaller shop is more likely to be a catch all of work types and not as efficient. (Think race car vs minivan).
The rule of thumb I use is based on SBA and SCORE classes for bank funding. The business goal is to keep direct labor's share of gross sales below 30%. So an employee at bare minimum must produce at least 3x their gross pay including employer costs, benefits, and contributions - which in reality is closer to 5x their take home pay for them to understand it best.
Keeping labor at 30%, and cost of goods at 20%, keeps the business in the minimum performance zone for a bank to loan to it. The 50% of gross remains to cover overhead, ROI on the initial business investment, taxes, interest, depreciation, growth, and pay the owners' salary.
Pay is always negotiable, but it helps to know what the average worker in your area makes, and how it relates to a generally accepted business model, both for employers and employees.
