I'm regularly being asked about buying, selling and valuing of calculators. I'll try to answer some of the frequently asked questions here. People are of course very welcome to contact me with questions, but often I end up answering almost the same as last time. So therefore this list.

How much is my calculator worth?
I've paid between 25 and 300 DKK, for most of my calculators. And the price has not always been directly connected to the state and age of the machine. But generally you can say that the price depends on the age of the machine, how nice it is and whether it works. And if the machine is special (design or functionality) it will often be worth more. The price also depends on where you buy the machine. A calculator bought at a flea market is often cheaper than the same machine bought at an antiques dealer.
Where can I buy/sell a calculator?
I've bought most of my calculators on flea markets and car booth sales. Some of my "pocket calculators", I've bought online. The challenge of buying/selling the "big" machines online, is that the freight often will be more expensive than the calculator itself. I only know of one antiques dealer that have specialised in technical antiques at that's Antique & Art in Viborg. I believe that most of the calculators I've seen at flea markets and at antiques dealers have been bought as part of a bigger consignment. You can always put up a calculator for sale on dba.dk, and then hope that there are some one close by showing interest.
Will you buy my calculator?
Maybe. If the calculator is in a good condition and/or don't resemble those I already have too much (I have to limit by collection, since I have limited storage), I may be interested.
Can I buy one of your calculators?
That's a difficult question. A collector normally don't sell anything from the collection. But if it's one of the machines where I have several similar and/or you need the calculator for something interesting, you are welcome to contact me.