This essentially is how tailscale operates (or did last I was in this space). Home/small use totally free, and experimentation seems encouraged.

> https://tailscale.com/pricing

I have genuinely deployed tailscale in paying locations on basis of my really positive experience on the "Personal" plan, which is effectively almost the whole product for up to three users/100 devices, for free.

I don't think there is a universally right answer for all products/services on this question though.