Ask HN: How much disposable income should you have?

I think you'll struggle to find a solid suggestion since disposable income isn't something people directly budget for; it's what's left over after you've ensured everything else is budgeted for.

The thing is, what is your disposable income for? Going out to the movies every weekend? If you enjoy movies that much, why not roll it out of 'disposable income' and into your regular monthly budget?

Or did you have a more refined definition of disposable income?

Are you wondering percentage wise or an absolute dollar amount for living in one of the top 10 largest cities in the world or US?

Dollar value of disposable income. Retirement is a good consideration (per the other poster), however I do have a pension plan, so I'm slightly less concerned about that.

Ultimately, I'm considering financing or leasing a (pretty expensive) car, and wonder how short I should leave myself.

you didn't mention retirement. That should be about 10% of your income.