Can I buy 1 dollar of Robux?

Excuse me, as a cryptocurrency and finance expert, I'm curious to know if it's possible to purchase just 1 dollar's worth of Robux? I understand that Robux is the virtual currency used in the Roblox platform, but given the way cryptocurrencies and digital transactions often work with minimum transaction amounts or fees, I'm wondering if it's feasible to make such a small purchase. Could you elaborate on the logistics and any potential limitations in purchasing such a small quantity of Robux? Thank you for your time and expertise in this matter.