I want to build an application and make it available for free but not sure how possible that would be

I am working on an application and I do not plan on making any money from it but rather have it for free for anyone to use. Should I worry about the stack that I will use to develop the web application? Also what are other things that I should keep in mind? I do not expect to have more than 100-500 monthly users so I would put that as a limit. In the end of each year I would not want to pay more than 500-1000€ to support all the costs related to it. Not sure if what I am thinking is possible.