Not really familiar with Doge, so someone else will have to help. Best to think of BTC not as each individual BTC, but as Satoshis, or SATs. When you get rid of the decimal, it makes everything easier. So 1btc = 100mil SATs. Since 1usd is 2200 SATs at the moment, you just do some basic math.
Hopefully you find someone knowledgeable about Doge. Good luck in your transaction
What crypto are you trying to pay in? If BTC, probably cashapp or strike (if available in your country) is probably the most straightforward. Be forewarned: both of these are KYC (know your customer) apps, so if you are purchasing anything that could be nefarious or illegal, you WILL get caught. BTC is very traceable unless you go through WAY more hoops and steps.
If you are looking for anonymous transactions and trust the seller, sending cash is probably the most anonymous without a ton of steps.
Its the small things, not anything massive.
For example, most toilet paper holders in Japan have this floating lid that sits on the toilet paper, which allows you to cleanly rip a sheet off every time, and prevent tearing a corner off.
The suica or iccoca cards (trains and subway cards) can be used to tap to pay near everywhere, including vending machines and such. Quite convienent.
You can pay many of your utility bills, in cash, at most main convienence stores. It allows for more methods of payment outside of everything tracked by credit card.
Many shower rooms ( Japanese bathrooms tend to have a full wet room for bathing) often have an advanced fan system, with a dehumidify option for drying clothes you hang in that room.
Many bathtubs have a water recirculate option, which reheats the same bathwater keeping it warm without needing to refill or add water to the tub.
Ah, one of my favorites is in many bedrooms there is a small square panel on an outside wall, and if you click it it vents to the outside, providing outside fresh air without needing to crack a full window. They often have filters built in as well.
Its becoming more common in the US now, but minisplit AC systems are ubiquitous in Japan. Its nice being able to control each bedroom separately.
I could go on. I lived there for a bit with my wife, in Osaka and in her hometown ( in Nagano).