please tell us the general type of business your trying to monitor. why don't you just go there and act like your applying for a job?
It is a transport business.
A bit of background: when I started scanning in the late 1990's, they had a licensed frequency of xx.xxxMHz which was registered to them "John Smith Transport".
In around 2003/2004 this frequency went dead. A few years later I found them using a shared repeater on xxx.xxxxMHz. This was licensed to "ABC Communications" but was being used by "John Smith Transport". I spent a lot of time listening to them to confirm this.
In the past year, this frequency has also gone dead, I suspect they have moved to a UHF simplex frequency which was used by another company which they purchased a couple of years ago, I can't confirm this.
Their depot is located at the end of a public road with no other businesses anywhere close by. Due to the nature of what they transport they get very nervous about anybody hanging around. If I had an easy way to do this I would be taking that path.