If you have an idea for a great service or application that solves a user problem, don't rush to invest in developing a fully functional product and get ready for months of hard work behind closed doors. According to the lean startup concept of Eric Rees, it will be much more efficient to answer the question: "Do users need this product?" MVP will help you with this.
However, often at this stage, there is a misunderstanding between start-ups and the companies they trust to develop. The misunderstanding has to do with estimating how much does a SaaS MVP costs.