Your agreement was $25/month, so if they start to charge you $120 you pay them $25 and then cancel the service. This is very annoying but do happen dealing with unscrupulous businesses. Although if they have 500% margin eg. you pay $5 for something you can get for $1 elsewhere they will care more about keeping you as a customer. Compared to for example a cloud bill, renting a VPS is both cheaper and more predictive. If you are however paying $25/month you should start looking at dedicated servers, where all resources are preserved for you.