This is a deceptively difficult task
Especially for an MVP, DO NOT SWEAT THE DETAILS of language, udnerlying architecture, etc.
Focus entirely on how you want the product to behave. Let the engineer choose how to do it *
If you're not a developer, you probably don't know what is "reasonable". Get a CTO friend to evaluate this for you.
There are a lot of great tools that you can use to help you mock up ideas before you ever talk to a developer. Use them to clarify your idea, test before paying money, and communicate your vision better.