Getting a raise in rates, changing some terms
For freelancers who work on their own, hourly or fixed prices are the most common pricing models. If you work as a freelancer through an agency, you can also get paid based on commission. Finding a reasonable price is something of a jungle. To know how much you can charge, it is good to benchmark against the market and see what other freelancers charge for similar services. You can gain bigtime by renegotiating with your current clients the rate you receive. Obviously, this has to be done in a long term context. When presenting your case for a new rate of pay, you can refer to the work you have already done and the efficiency of you delivering as per your contract.
Perhaps you have a way to show the work has become more complex? Perhaps there is more work and delivering on the project demands more of your hours and time and you need to be compensated for that. Additionally - over time - all costs rise. If you are a freelance designer and you have been working for the same client for two years, there has likely been a market increase in your off-the-shelf services rate. Not to mention, because freelancers are something bigger businesses are coming to rely on more and more, they are allowing more room in their budgets to pay fairly and even in some cases handsomely - as they would with long term employees and so forth. That is part of your bargaining as well - you are not a long term employee. You can not just absorb the rising costs of your own contributions and a business minded business would understand that.
However, it is true that older businesses approach freelancers like it is the buyers' market and they think that they can set what price they want for items. At the same time, some clients have a superstition about how quickly an article can be written, as an example. "You can write that in an hour," they say, believing in earnest that it is so. Anyway: The trick is to tell you what takes time and why you have to bill what you want (it often doesn't mean you have to take care of yourself and pay for insurance, offices, etc. and definitely not that you have to pay for days when you are not selling…). For example, you might say: "Unfortunately, it's a little too low - it takes time to get into the topic, book interviewers, go and meet them / book a phone interview etc. What about xxx instead? ”.
Just as you would rather buy a phone subscription that gives you unlimited everything or special bonuses if you buy this particular phone, clients want to pay more if they feel they are getting a good deal. And it's up to you to tell them! After you have justified what takes time, say / write: “I can do it for xxx but then you also know that you get a really good text that you hardly need to change a word in and that you can pass on to layout on right away"
Know where and how you can create a better situation for clients, and offer them a better deal so they feel like they are getting a better deal! Clients are often interested in maximising expenditure and the time of renegotiation is the best time to bring these kinds of ideas to the table.
Another area to consider negotiations is in copyright. Copyright is important to keep in mind when signing an agreement. The scope of the publication can be, for example, "Once in the magazine XX" or "Once in the magazine XX and on the XX website". If you transfer the rights in any way, remember to specify fees for that as well and that it is clear what is included. Also, remember that no changes may be made to the submitted material without your approval, it can also be good to bring along to be clear.