A lovely two bedroom apartment in a central location - most of the major tourist destinations are no more than a 20-40 minute walk away. You can walk via the river a short 40 minute walk to Vatican City, and the Colosseum/Palatine Hill is only 20 minutes away.
In terms of getting taxis, the most we paid (going to Vatican City) was 12EUR, which is quite cheap via itTaxi. There is also a bus stop directly outside of the front door of the apartment, if you can figure out the bus routes.
The airbnb itself was lovely, the tree-lined street it's situated on very pretty. The neighbourhood is a markedly non-touristy area, and the local restaurants were all very good and also very cheap - it felt like an area that people actually lived in, rather than the vibe of a tourist trap, which I vastly prefer for a city break!