There’s a wiki for different parameters in the URL
https://forum.inaturalist.org/t/how-to-use-inaturalists-search-urls-wiki-part-1-of-2/63
I don’t know the answer to your lifelist question
Adding new places is generally only a problem if they are very large places (or smallish ones that happen to have a whole lot of obs). Alternatively you can draw rectangles and circles on the map to restrict your search to that area and bookmark the URL for reference later.