WTF!!!No Bondi Beach? No Maroubra beach? No Manly beach?

OK I want buy a water front and I am prepared to wait but how far above current levels should you go so if the sea does not stop rising to end up with a water front in say 12 years?...
Half of world's beaches could vanish:

Climate change and sea level rise are currently on track to wipe out half the world's sandy beaches by 2100, researchers warned Monday.

Even if humanity sharply reduces the fossil fuel pollution that drives global warming, more than a third of the planet's sandy shorelines could disappear by then, crippling coastal tourism in countries large and small, they reported in the journal Nature Climate Change.

"Apart from tourism, sandy beaches often act as the first line of defence from coastal storms and flooding, and without them impacts of extreme weather events will probably be higher," lead author Michalis Vousdoukas, a researcher at the European Commission's Joint Research Centre, told AFP.

more at link....
Sandy coastlines under threat of erosion:

Sandy beaches occupy more than one-third of the global coastline1 and have high socioeconomic value related to recreation, tourism and ecosystem services2. Beaches are the interface between land and ocean, providing coastal protection from marine storms and cyclones3. However the presence of sandy beaches cannot be taken for granted, as they are under constant change, driven by meteorological4,5, geological6 and anthropogenic factors1,7. A substantial proportion of the world’s sandy coastline is already eroding1,7, a situation that could be exacerbated by climate change8,9. Here, we show that ambient trends in shoreline dynamics, combined with coastal recession driven by sea level rise, could result in the near extinction of almost half of the world’s sandy beaches by the end of the century. Moderate GHG emission mitigation could prevent 40% of shoreline retreat. Projected shoreline dynamics are dominated by sea level rise for the majority of sandy beaches, but in certain regions the erosive trend is counteracted by accretive ambient shoreline changes; for example, in the Amazon, East and Southeast Asia and the north tropical Pacific. A substantial proportion of the threatened sandy shorelines are in densely populated areas, underlining the need for the design and implementation of effective adaptive measures.

Don't panic, some 3 billion years ago, the world was just water with no visible land. So beaches come and go.
Executive Summary:
Awareness and a partial understanding of most of the interactive processes in the Earth system that govern climate and climate change predate the IPCC, often by many decades. A deeper understanding and quantification of these processes and their incorporation in climate models have progressed rapidly since the IPCC First Assessment Report in 1990. As climate science and the Earth’s climate have continued to evolve over recent decades, increasing evidence of anthropogenic influences on climate change has been found. Correspondingly, the IPCC has made increasingly more definitive statements about human impacts on climate. Debate has stimulated a wide variety of climate change research. The results of this research have refined but not significantly redirected the main scientific conclusions from the sequence of IPCC assessments.

Some science.
In geological terms, we are only around for a billionth of a second, so the foreseeable future to us is totally irrelevant.
True. But still, I bet you'd get mad if someone was about to kill you or your kids - even though you (and they) are around for effectively zero time in geological terms.
About 1.5 inches.
Some places the sea level will drop. Any places the sea level is due to rise, multiply the predicted (best estimate) by the extreme factor - often between 3 and 12 - indicated by the current working model (to cover tidal effects, erosion, compaction, etc). That will give you a sort of average high - then calculate the storm surges etc expected from that base.

The average global sea level rise hardly matters, if you're buying less than a thousand miles of coastline or so.
In geological terms, we are only around for a billionth of a second, so the foreseeable future to us is totally irrelevant.
The rest of us, not being rocks, do not live in geological terms, but in human lifespan terms - the foreseeable future is far more relevant than the geological one, for us.