Before considering nursing homes, one has the option of needing to consider retirement homes/villages (which have both independent living places as well as high care need places).
To gather an idea on potential cost for nursing homes (as they will go up), read this and use the figures:
Nursing Home Costs
Everything that you save in reduced costs are likely to be spent in aged care fees. The lucky few are physically and mentally capable into their late 80's. Depending on the level and type of assets and the position (one person of couple needing facilities, or both); means much research should be considered before making any decision.
I had one couple where the husband needed nursing home facilities (as assessed by ACAT) after a stroke and the wife needed to withdraw from her Allocated Pension to partially fund his Refundable Accommodation Deposit (RAD, previously and more easily known as the "bond"). She then sold their home and that funded her into her independent living unit (at the neighbouring retirement village) and allowed her to put the equivalent funds that she'd spent on his RAD, back into her super.
The average time spent in a nursing home (previously known as high care) is 1 years and 3 months (as most are in serious decline health wise, it makes sense). My client died after 6 months and the RAD was refunded to his Estate and then available to his surviving spouse (who was the major beneficiary of his Estate but by this time couldn't put it back into super as she was then over age 65). So we had to use other retirement income steam strategies for those funds.
Understanding RAD's and Daily Accommodation Payments (DAP's):
Making sense of RAD and DAP | Aged Care Online