The cost to go off-grid will depend on your expected/anticipated energy demand. With knowledge of your energy demand we can then help you size your battery storage, solar PV, generator, microgrid inverter, etc.
It is worth noting that connecting a new block to the power grid can cost between $10,000 and $30,000. And a typical energy bill for the average household is around $3000-$4000 per year (or higher in colder areas). Given the cost of grid connection and supply, a well maintained and high quality off-grid system is likely to be cheaper in the long run (20 years +), depending on your particular situation.