Well, after my rant about analog scopes on Europe, I found a Tektronix 2246 almost locally. Seems to work, owner provided pictures with traces on the screen. €200 sadly, but hey, after seeing how much is asked for 20 MHz Hamegs I'm considering it. I'm told it hasn't so many unobtanium hybrids inside. Will see.
For OP, there are some real cheap oscilloscopes, two of them could be enough for more advanced projects than the one it already is in:
Zeeweii DSO154
https://aliexpress.com/item/1005004972406356.html can also be bought with battery and probe. Battery runs out quickly, so if one has a probe, it could be wise to bought the cheap version, whose hardware is absolutely identical, and get a battery with more amps/hour. Since it has only one channel and just 18 MHz bandwidth, it would be recommendable only on a very low budget and under the circumstances already expressed by rstofer. About €40 with battery and probe.
Zeeweii DSO2512
https://aliexpress.com/item/1005003085753955.html Thats the one aldo22 suggested. aldo22 and I are getting a lot of fun with it (altought I don't even own it). We also already learned a couple things about aliasing, etc. Double channel, seems that it could do at least 20 MHz with both channels, perhaps 40 MHz. It's battery is said do be quite a lot better than DSO154's. Link to the relevant thread was already provided by aldo22. About €100
Somebody suggested an Owon handheld, I think he's was suggesting HDS200 series. Low end model would be HDS242, dual channel 40 MHz, it has 20 MHz bandwidth limit button (so looks more serious than Zeeweei's models) and it's also a 20000 count multimeter. Other models go at least up to 100 MHz, even higher than that, and can include also signal generator. However HDS242 could be the same that HDS272 without even unlocking?
Not really sure about that, and higher models could go up to €200 and more. At that price range an old analog could be found near that price?
It seems that most software bugs have been already ironed out. However it also seems that it gets hot after some minutes powered on and recalibration is often needed. Firmwares available, while (somewhat scarcely) provided by Owon, are heavily model and even serial number dependent. And it comes with just one probe. This is the forum thread about it (26 pages):
https://www.eevblog.com/forum/testgear/owon-hds-200-handheld-oscilloscope-w-builtin-dmmawg/ HDS242 is about €125. Can be found here:
https://es.aliexpress.com/item/1005005174220079.html