I got to talk to a client who wants to have an app for his restaurants. The app should include a ordering process as well, for take aways. But I am not sure what will be my to-do list in that kind of project. So I can estimate what to charge. Does anyone know where to find a general checklist for a freelance job? Then I can better estimate the price and explain what is behind it for the customer.
I agree with @halfer's comment about this question being broad and may not be up to community guidelines but I think this is a question worth having an answer to that can be helpful for all industries.
Know your work
You're being hired because you're the specialist/expert in your field, not them. 9 times out of 10, then client has no idea what they really want or the scope of what it will take for you to complete a certain task. If during the interview you're asked "How much would you charge for x" you need to at least be able to give a ballpark answer.
"Based on previous work I can estimate this will take x time and my hourly rate is y/and I would charge z for the project" but don't set this in stone. You should get a detailed list of what the client expects - no two projects are the same.
"Feature A is a complex task that will add an additional X to the cost". This is particularly important for software. Based on what the client wants you can research how difficult getting results will be and the time commitment it takes.
There's no reason there should be a "general checklist" for how to do your job, if you need one then you're not ready to freelance.
You're the expert and you need to be ontop of your work. You should have a general idea about how difficult tasks are and the time commitment they can take. Use this knowledge to give a ballpark estimate and then do research in order to give a hard cost estimate AND time estimate.
PS: if it will take 3 months to complete, tell them it will take 4. This way if things take more time you're safe and if things go according to plan you'll be done a month early.