"I would be most worried about rest areas, dog parks or exercise areas, pet stores... I would avoid those areas and interacting with unknown dogs (unknown vaccination status) as much as possible until the vaccination series is complete."
As would we. That was the reason for the question about carrying caution one step further.
The pup will be 10 weeks old with two vaccination shots of the series. At that time the pup will have some resistance remaining of the 22 weeks that the mother's vaccination provides to the pups.
The bleach solution did not kill my grass. We do not intend to put the bleach solution into a consumable or damp contact state so "poison and kill grass" seems to be a bit of a hysterical stretch for advice. Bleach use is common in hospitals, clinics, restaurants, and I suspect vet offices.
We have decided to use an outdoor carpet under the pen to avoid the pups contact with the soil. She will not be on walks, associating with other dogs, or on the ground outside of the matted pen. We will not be in the pen so tracking there will be limited.
But inside the MH things will not be so pristine as parvo contamination was not part of our concern for the past 12 years with our previous dog.
I realize there are no guarantees, that is why I asked if anyone had a failure in a similar process.
That was probably a silly question which can only be answered by dire warnings.
Thank you for your responses.