At 40s, only purchase a house / property on loan if you already have that amount in your investments. Don't stress yourself with 'potential future income' to cover the loan. Chances of retrenchment, role being obsolete / redundant is pretty high the older you get. You might be the best employee in the company today, but down the road there is always a younger, cheaper version of yourself going to fill that role of yours.
There is no such thing as 'company needs you to survive'. The moment you are a burden,  off you go.