What are some ways to monetize a 'non-profit' website?

By monetizing I don't mean "make tons of profit", but enough to keep the site running.

I'd like to donate my time (programming hours) to build a platform that connects animal shelters and independent rescuers with people that would like to adopt or serve as a foster home. I will need to store tons of pictures (maybe in AWS S3) and build authentication.

I know you can get really cheap hosting with MySQL and PHP. But I want to use NoSQL (maybe Firebase), NodeJS and ReactJS because I want to get really good at those, since the best way to learn is by doing, I figured why not build something that will make the life of volunteers easier while promoting adoption instead of buying.

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Costa Rica does not have any real animal protection laws just yet, so mistreating or abandoning an animal comes with no consequence.

ps. Meet Noche (means Night in Spanish) we recently adopted her, she had scabies a month ago but after treatment she's looking really pretty now! :)