Basically I have done work previously for my client and he wanted a 3 page basic website in HTML/CSS and we both agreed to a fixed price of £350. Now a year later I have received an email from him wanting the site to be a bilingual site with external language files coded in PHP. They have provided me with the translations but the work I have done so far is more than what I have originally charged them?
Should have agreed a price before you started and agreed on an hourly rate if unsure how long it will take.
Everyone is different with prices, depends on your expenses and other income sources. Ultimately it’s up to you to decide how much your time is worth – something mundane like adding different language support to an existing website should be pretty easy if the infrastructure is already in place, although it does sound incredibly boring.
Tell him plain and simple you’re expecting more because you’re doing more work on it, take it or leave it. Chances are he’ll stick with you because he knows you’re capable, reliable, etc. I wouldn’t charge much more though.