Other validation methods?

Hello indie hackers!

I'm working on creating an app that will allow parents of special needs children to have direct on-demand access to sitters who are trained and qualified to care for their child's unique conditions. Recently, I did some validation using the 'fake door' method where I set up a landing page and ran Facebook ads to it for 5 days. My goal was to see how many people would actually click on the 'Join now' button. My results after 5 days were the following:

• 21 link clicks to the landing page
• 8 converted to leads
• 38% conversion rate
• $35.65 spent on ads
• $4.46 per click

I think those were pretty solid numbers given that I am planning on having a subscription model for the parents, charging $49/mo, $99 for 3 months and $249 for 12 months. So even a user paying $49 a month, having a cost per click of $4.46, that would mean a ~$44.54 in profit for that user.

Taking this as a good initial validation, I’m now thinking of other types of validation that I can do, such as talking to parents with a special needs child and talking with professionals working with special needs children. So far, I have a full clickable high fidelity prototype built out that I can show to potential users (both parents and sitters) to have them use it to give feedback. Are there other types of validation that you all would recommend given that this would be a two-sided marketplace?

Also, any feedback on my results from my landing page or on the idea, in general, are welcome!