You only have to check the GPS position in your mobile phone and enter those values if you scan from home.
You can never decrease the values for range to scan a more local area, you can only add to what are already set in the database. The theoretical range set in the database for each site could be way too far away and not what you want to scan. But then on the other hand I see a 122MHz frequency for arrival/departure in Kansas that are set to 0,5 mile. Then you have to resort to favorite list scanning, exporting from database when the range are set to max and then delete or avoid systems or sites that seem to be not local, requiring a bit of knowledge of your own.
To sell or supply a ready made list you will have to use something like ProScan and check the range of each site and department to see if it looks realistic and there are some errors in the database that needs a person to scrutinize that data for a site and TG's and compare to a geographical map. A lot of work that I do not expect those custom list producers to actually be doing. They asume that the database are 100% correct for all kinds of use, scan from home or mobile.
The best way to copy from one brand of scanner to another would probably be to just copy & paste between the programs for frequencies, text tags and TG's, that you can do in big chunks at a time, and then edit all other parameters.
/Ubbe