How much does a house cost? In Sydney perhaps $900,000, in Cooma maybe $250,000, in Afghanistan maybe $20,000 ( I don't really know the cost in Afghanistan).

There is no correct answer here.

The cost of a court case depends on how much time your lawyer(s) spends on the case, and the lawyer's charge rate.

The time depends on what is involved, how complex the facts are, whether the applicable law is clear, what court or tribunal it is in, how the other side behave, and numerous other factors.

You have to pay your own lawyer(s). You may get an order that the other side pay say 80% of that if you win...but the other might not have the $, or go bankrupt (eg in USA recently, someone called appropriately "50 cent").

If you lose, or even if you don't win more than an offer made by the other side, you may have to pay say 80% of their legal costs.

Your lawyer must give you an estimate of your own costs when that is possible. That will be after the lawyer knows a bit about the case. Estimates should be revised by your lawyer if there is any significant change.

Court cases should be treated like placing a bet...look at the odds of winning and losing, the $ outcome for a loss and a win (including legal costs), the emotional and time cost to you, and then make a calm and rational decision whether to place the bet.....OK, that is not what people do when they place a bet, but it is what they should do.