Your method makes perfect sense, I can find the pointers to any of those lines now. As you said, changing the pointer of the next line to a further address leaves more room for the line I want to edit. The problem is I'd have to rework the next line in a way that is functional and still makes sense in-game. So that's another can of worms...
In theory, if I can change the "2,000" to "1,500" while still keeping within the confines of the original pointers (equal or shorter than the original text, like you said), it would be the perfect solution. In that case, though, I'd still have to figure out what bytes of compressed text become "1,500" when uncompressed. To that end, I tried looking into other compressed text strings that contain "1,500" when uncompressed in-game. Example:
The power be with you for 1,500 nuyen!
I tried copying some of the bytes from that string, in hopes of getting that 1,500. None of them worked. It's like each string of compressed text uses its own codewords, I'm not sure...
Your other suggestion sounds more feasible, maybe I should expand the rom and write my own uncompressed text separately. If I were to change the routine that points to that original line (making it point to my custom line in the expanded space), would the other lines in the game still work normally? IOW, can I change the routine only in regards to that specific line?
Thanks so much for your help!