This apartment is excellent: Comfortable beds, modern kitchen and bathroom. Altho we didn't spend so much time there becasue Naples is so great.
Centrally located in the Spanish Quarter, all areas are walkable: Via Toledo (nearest Metro) the Old Town, The Port.
We felt very safe and enjoyed a different restaurant for every meal, of which there appear to be hundreds.
As it is centrally located it can sometimes be very noisy but we read this on the reviews before we went and took ear plugs.
We got the train to Rome for the day. The boat to Ischia for the day and booked an organised tour to Pompei for half a day.
Covid
We took our 12 & 14 yr old who cannot get the Green Pass because they are not vaccinated. They had to evidence a negative test every 48 hrs for entrance into certain places, but there are pharmacies all over offering the test for €15, they give you a paper certificate as evidence. We didn't need to keep getting tested because we had the NHS app that qualifies for the Green Pass.