Hi guys so I have recently gotten really interested in gmrs radios. After owning my Radioshack Pro-164 scanner for about 3 years my interest in radios has greatly increased. My first step into an actual radio will be GMRS. So am looking for a budget GMRS radio and antenna. I will be using the radio in my vehicle and maybe in my house temporarily at sometimes. I do not want to drill into the roof for an antenna so I will want a nmo magnet mount and a good antenna. I know that this has been posted a million times but things change and new radios come out along with many other factors so any help would be appreciated. I will mostly be communicating with my buddy who is about 6 miles away from my house(I am at a higher elevation than him, no tall trees or buildings but some rolling foothills) but at the farthest I will be about 18 miles away at at least 1500 ft higher elevation than him and in the mountains with large hills and tall trees. I know that might be pushing it but thats ok if I can't do that. Anyway thanks a bunch
Impossible to say if that's realistic or not without more information. 1500' above your buddy is great but not great if there's a 3000' peak in between you. Or maybe even another couple of miles at the same elevation. UHF is not very forgiving when it comes to line of sight. If you can see it, you can hit it, give or take a mile or so of trees and buildings. (That's my general rule of thumb)
But lets talk about the logistics of using a portable in the car with an external antenna.
Portable radios aren't designed with the connection to external antennas in mind. The antenna connectors are usually a weak spot.. And if the plan is to frequently connect and disconnect when you're in the car, you're going to put a lot of stress on that connector. And to make matters worse, you're probably going to end up placing the radio somewhere in the vehicle where it will see even more stress on the connector. Chances are it if is a budget radio, it's not going to have an available device to convert it to a mobile running off the vehicle's 12v power. Which means you're going to have to be forever removing and replacing the battery and/or the entire radio putting even more stress on the antenna connector.
I know a lot of people that are new to the hobby (both GMRS and amateur radio) expect to have citywide in-vehicle portable coverage with rubber duck antennas but there's a reason you don't see business and public safety users doing that... Because it doesn't work.