"Eventually, by being unemployed they would not be able to cope with their living expenses."

Question

Could I say the sentence below?

"Eventually, by being unemployed they would not be able to cope with their living costs"

or should I use "could not" instead of "would not be able to"

Does it make sense at all?

Answer 1

Yes, you could say the sentence below -- albeit with a few minor adjustments.

The following sentence would be correct: 'Eventually, by being unemployed for a long enough period of time, they would not be able to cope with their living expenses.'

The part in italics is necessary because you need to give the cause of the draining of their money and the fact that they can't afford their living expenses. It is not because they are simply unemployed, but it is because they are unemployed for a long enough time that they no longer have enough money for their expenses.

Using 'could' here would just not make sense as you are talking about them not being able to afford their living costs because your sentence would be (if you used the substitution that you proposed) 'Eventually, by being unemployed, they could cope with their living costs.' This conveys basically the opposite of what (I believe) you are trying to say and additionally does not make sense at all.