I don't see how I can commit to any project where the abuse is clearly on the side of the person who desire to obtain photo without paying any money
Are you saying you gain nothing or very little from having a model you can practice shooting and trying different lighting setups etc?
I suppose the comparison would be how much would a model charge you if you were to hire them?
I think you need to agree with the model that whilst you will try to get shots following their brief they should be open to you directing them so you can learn new techniques. They may want certain types of in studio portfolio shots whilst you want to practice shooting in urban landscapes. These are the kind of things you need to agree with them up front and get them to sign an agreement where you commit to deliver a set number of shots for their portfolio and they commit to a certain number of hours of modelling under your direction.
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