It is important to clearly understand what tasks you are setting at the start, so that you don't waste money on unnecessary things. Some companies may offer a full development cycle, but you need them to understand exactly what you need for testing an idea, not for a full-fledged product. I've come across a team that worked according to this principle and didn't impose unnecessary things. Here, for example, is a firm for MVP development at this link, you can take a look.
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