Communication is critical for Neighborhood Watch programs. Imagine being able to assist in a time of need, but not be able to notify anyone or call for help.
There are a few levels of radios you may consider. In the past, a typical setup may have been with Family or GMRS radios. However, over time, these radios were seen by most to be merely a step above being useful toys. They worked great for a few weeks or months, then fell apart or would not take a charge. The reason for this is they are cheap, but cheaply built and never meant to do more than go to the mall with the kids or maybe go hunting on occasion.
However, today's business radios have replaced these as the go-to model for any neighborhood watch program. The radios are durable, the range is very strong and the batteries are Lithium-ion, the best battery on the market, which will typically last years. There are three models shown below. All will have enough range for a standard sized neighborhood.
But, the stronger the model, the more coverage, even if someone drives out of the neighborhood. While the CLS model is the least expensive, it is probably the most cost-effective solution. But the RMM2050 model does not require an FCC license and is a 2 watt VHF, vs 1 watt UHF for the CLS. The strongest handheld would be the RDU4100, which is a 4 watt UHF. Many communities will spend the additional amount for these, especially if the area to be covered exceeds a square mile.