I do not think I will buy bitcoin if the price reaches $ 100k, because it is very expensive and I should look for bitcoin through signature campaign. In signature campaigns by getting bitcoin will be very profitable and I will start investing after I get bitcoin.
A lot of people are always complaining about expensive, but they have failed to understand that even as at now, so many people are still considering bitcoin's value to still be expensive. So, when will the whole expensive thing stop ? When 1 satoshi is equivalent to a dollar ?
No one knows the peak of bitcoin but as long as I have vision for just those tiny satoshis and the fact that bitcoin will be very useful in the long run, and then I am still going to buy even at $1m.
Even at $100k value, a lot of people will still be buying bitcoin. I see that by then, hopefully a lot of things would have changes, most especially in the usability of bitcoin and that would have really made the value to keep skyrocketing to the point that people won't really bother the amount they are buying as long as it is useful, there is value for it. So far, Zimbabwe has really thought me that, even at a higher value, as long as people need it, then it is non-stop.
I think most people are just worried about when the potential for more profit will end, there is an upper limit after all. I will however still be buying at $100k, but probably not at $1m. For some like me it is an investment rather than purchasing into its utility because right now bitcoin is failing to scale up to mass adoption.