All of Waikiki is a densely populated area, It's filled with tourists, as well as local residents. Unfortunately, there is some prostitution, as well as some theft in the area, because of these factors.
There is a very large emphasis on the 'State level', to make sure this area is safe, for tourists, so there is a very large presence of uniformed and undercover police. This particular property is just 2 blocks away from the Waikiki Police Station, as well as the beach. So, it is relatively safe, but you are looking at a very densely populated area. It is also a very good area to invest in for rentals.
Hope this helps.