whatever you prototype - the one who built it in 6 month will have economy of scale to make it cheaper than your diy solution, and because they serve many customers and developed it for 6 months - their product will be 100x better than the one you diy

there is very very rare use case when diy makes sense. in 99% of cases its just a toy that feels nice as you kinda did it. but if you factor in the time etc it is always costs 100x more than $5/month you could usually buy