What's wrong with a little Krups grinder, a cafetiere and a kettle?
There is nothing wrong with that. This is rather similar to the method the professional coffee tasters use.
In short, you get a container (a cup will do), you put in some ground coffee (between 6 and 7 grams per coffee) and you pour hot water. Below is a Youtube video, the interesting part is at 1:06
That is the best method for testers but not for the ordinary drinker because you have to be careful otherwise you can drink some of the coffee powder. You can wait a little while to let the coffee settle at the bottom but at that stage, the coffee will be lukewarm.
A more practical way for coffee drinkers is this machine
https://www.maxicoffee.com/en-gb/di...oTfy30Xc-_SeUkdLhcvK4u4sovx_Rf5hoCoVoQAvD_BwEor if you can find it this one
https://www.amazon.co.uk/Bialetti-E...d=3df8abefd2e8301d8efe082170e14ecf&th=1&psc=1The cafetiere mentioned above will be just fine too.
You will not have any of the drawbacks of the first method.
Costs
The first method has just the costs of the coffee, water, and energy to bring the water to a boil. In Tesco the average is £6.00 per 450g. If we use the recommended quantity of powder per coffee of 6/7 grams this equates to £6.00/450*6.5=8p per coffee approx.
The second method has the initial cost of one of the machines (around £ 20.00 each) and the costs of the coffee as above.
Maintenance
In the first method, there is no maintenance as you just wash all the containers.
The second method, you just rinse the machines with your fingers, no soap, no dishwasher. If you have flowers/plants you can put the coffee in the wase because it is a fertilizer.
The Bialetti has a rubber seal and you should replace it if it burns. This may happen after 10 years (I bought mine here in the UK in 2015 and it has still the original seal). The first machine has no seal instead.
My father had three Bialetti machines in all his life and he passed away when he was 86.
He changed the first one because he was tired of seeing it, and the second one was replaced because he put it on the stove, left it on for 20 minutes, and the handle burned.
As a side note, my father was a master coffee roaster by trade for over 40 years. I did the same job for 3 years.
Alberto