Dartmouth BASIC had a renumber command. I believe that line renumbering commands and/or utilities were commonly available for microcomputer BASICs as well.
Some BASICs had a RENUM command. They were a bit of a pain as well. As you wrote your program you got to know which line numbers were associated with which statements. Doing a RENUM meant having to relearn the "meaning" of each line number. I'm pretty sure my VZ-200 didn't have the RENUM command.
Yes, most Microsoft ROM BASICs at least 8K in size had the renum command. It was still a pain because you had to figure out the start, end and skip values.
