Be”H we shall be selling our house because we need to go to a sheltered housing complex due to medical problems.
We shall pay two thirds of what we receive from the sale to the complex to ‘buy’ an apartment but the monthly ‘maintenance’ payments are very high and we shall need to use both our pension money and part of the remainder of the money from the house to pay it each month.
We shall probaby have to invest the remainder of the money to use the interest to help with the monthly payment.
From what amount of money should we deduct maaser.
From what you are writing, it doesn’t seem that you have to take off any maaser at all. The two thirds that you are giving to the complex, is like selling one house in order to buy a different one to live in. Even the other third is needed for the upkeep of the new apartment, therefore you didn’t really gain anything monetarily by selling your house.
You should both have arichus yamim, and enjoy good health.