"Frequently" as in several times over a short period, not as in over a
long
period. That makes sure we didn't miss any spots, and gives it a chance to
get all the urine.

You NEVER get ALL the urine. Animals sense of smell are hundreds if not
thousands of times better than ours. They can smell urine in the breeze
from an animal a mile or more away. Some of the cleaning products you speak
of will help over a period of time, but it never completely comes out.

Ask any crime forensic specialist.

Steve