The good thing about base-station and two-way radios is that they allow you to extend range by using an external two way radio antenna . The base station units have what's called a BNC connector that enables you to twist off the antenna that comes with the radio and then twist on a new antenna connected to a cable.
You will get noticeably better results and more range with your radios with an external antenna, especially if you can place it high. It is the single most important factor in increasing transmitting and receiving range of a radio. You'll need to make sure you choose an antenna that is specifically designed for the frequencies and application you are using and then choose the best location possible to install it.
For MURS radios, the FCC limits antenna height to 20 feet above a structure (exclusive of the tower, mast or pole on which it is mounted), or 60 feet above ground (whichever is greater). The higher you place your antenna, the greater range you will get. If you mount an antenna on your vehicle and connect it to your mobile MURS two-way radio, the higher you place the antenna on your vehicle, the greater range you'll get.
If you are using a handheld radio and walking around with it, you can't very well use an external antenna. You may be able to extend range by installing a better antenna than the one that came with the radio, but keep in mind that the antenna that came with the radio is "tuned" specifically for that radio. If you put on an antenna that isn't properly tuned, you could lower range.