Hey, don't worry I'm also ignorant, I honestly don't know much about anything
I used a wifi calculator, dBm to milliWatts conversion.
Well I hope you're right tbh.
Edit: You could get an amplifier, I recall -=Xploitz=- having success with an amp.
What antennas do you currently have? Grid antennas are highly recommended 24 dBi +. The very powerful omnis are quite pricey afaik.