This was not a hoarding situation; however, the scent of bad hygiene gained strength in recent years. 

Its about $6K, that is if they didn't break the sewer line with the “feminine items” they were flushing that caused repeated blockages.I plan to sue them in small claims but there must be some way to track their new address.Is there a way to use “skip tracing” to find them?

COVID is not very communicable on surfaces, so proper hygiene and sanitization of the bathroom should take care of risk of transmission there.

Having feminine products is always going to leave a great impression.

Unless you suspect there is a willful neglect, bad hygiene or mental health aspect that caused the bed bugs and wasn't just bad luck, don't evict; have them do a written payment arrangement.

Also, have a hygiene clause in your lease, not everyone has the same bathing standards as you. 

Install bite traps even if the house hygiene conditions are so badBroken basement stairs5.

When it was a rental, the tenants had a history of flushing hygiene products and clogging the sewer.

How do I broach the subject with my ground floor tenants that they need to do a deep clean and keep their apartment hygienic? 

This makes it easy to find the perfect tile flooring for your needs.Hygienic: Tile flooring is hygienic, as it doesn't trap dust, dirt, or allergens like other flooring materials.