This might not be a useful answer for you, but are you sure any of that is necessary? You can spend months pre-validating an idea and never get anywhere.
Go talk to potential customers now. Find people who are willing to pay for what your are going to build. Once you know they exist, then you can start worrying about market size and the rest. At this point having real life people who want to pay you is infinitely more valuable than any hypothetical data and analysis.
Go talk to potential customers now. Find people who are willing to pay for what your are going to build. Once you know they exist, then you can start worrying about market size and the rest. At this point having real life people who want to pay you is infinitely more valuable than any hypothetical data and analysis.