Is there a ceiling limit on what you are willing to pay for an audio component?

The simplest answer is that I pay what I can afford and what makes sense given the rest of my system.

Since retirement I buy almost 100% used. There is always someone selling last year's model at a discount and any well-reviewed component is still a quality component a year or two later.

The limit is, can I hear a worthwhile change for the cash. Sure, I'll hear a different between $5K and $30K speakers, but is it worth 6 times the price? Maybe, maybe not - I have to hear a level of improvement to make it worth it. Also, I wouldn't match a $100K amp with $10K speakers. The system overall has to make sense. 

When I first started reading the OP, I thought the right answer is “whatever your budget allows”. But then I read this, and was confused:

For me, I cannot see myself paying over $5K on speakers and likely not more that $3K on any other component.... even if I had the kind of money Elon Musk has.

I thought for a bit, and it hit me: it makes sense. I would not pay even a few hundreds of dollars on a designer handbag, even if I had the Elon Musk money. Because handbags are not my thing. Maybe audio is not YOUR thing?

So I guess we are now down to wanting to find out who are rich, super rich, less rich, somehow rich, poorer than rich and making ends meet. Too weird for me.

Again, money has nothing to do with sound quality.