I am a newbie and I want to know how much should I ask from my client. This is a math book project I started via milestone since April 4 as indicated in my contract, so far I have completed 6 projects already but I think it's not getting fair for me. At first, they offer me $15 per 100 pages but when I'm about to finish my first one they asked to make it 150 pages retaining the offer of $15. I don't want to complain as this is just my first job and don't want to ruin or affect my reputation so I complied. On the next few projects, gradually they gave not one but more sample designs of math book without increasing the offer which supposedly one at a time only. Still, I did not complain even though I started to feel demotivated this time because it's roughly a week to finish each project but the offer was so little. Now I have a current project with 9 sample designs and they increased the offer only to $25.
Please help and advise what should I do. I requested more increase but they refused.
YOU are the freelancer. YOU need to manage your contracts. Upwork can not do that for you. The client is not going to do that for you.
You, the freelancer, decide what is acceptable to you, and what is not. You decide what a fair rate is for your work. You decide what will be in a contract, what work you will do, etc.
If you do not like working for this client, then you do not need to continue working for him.
YOU need to be the one who tells the client yes or not. You can ALWAYS say "yes", but on your terms. Tell him:
This is a great idea. I think we should definitely add this to the project. It was not part of the original milestone description, so I can not do that as part of the current milestone. But if you add a new milestone for $X.00, then I will go ahead and do that. Or you can close the current fixed-price contract and start an hourly contract at my posted rate. Then I can work on any of these additional tasks without needing specific milestones created."
re: "Please help and advise what should I do. I requested more increase but they refused."
Your rate is your rate.
We can not tell you how much you should charge.
But if you tell a client how much your rate is to do Task X, and the client refuses, then THAT IS FINE.
The client can hire somebody else.
If the client refuses your rate, then you do not do the work for the client.
You will work for other people who will pay your rate, and the client will hire less-qualified people who will do the task for the lower amount.
Bernard, you need to stop working for this client unless she decides to pay you more. She's paid an average of $0.73/hr for 46,856 hours. That's not a client you want to work for unless she's the last client left.