I need a new amp. My budget is around 500€. I prefer tubes and it should have 20 -30 watt because I play in a band and some small gigs. I want clear cleans which sound good with a strat. I play in a rock cover band so the overdrive channel should be versatile(nevertheless it would be nice if it could reach Iron Maiden gain amounts). AND The amp should love it to be cranked

I already looked at some amps:
Hughes Kettner Edition Tube 25(20 watts)

Peavey Classic 30

Please suggest me some amps
The H&K is probably your best bet in that price range.

The Classic 30 might need to be boosted for modern rock tones and for stuff like Maiden. A C30 is 600€ new though, no? You might consider a Laney LC30 instead, same price but no need for a boost most of the time:

Or a Laney VC30, which imo has superior tone to the Peavey, but would need to be boosted just as well:

Tone's a matter of preference though, so make sure to try anything before buying.

If going used is no problem for you, maybe look at a Marshall DSL401 or Engl Thunder, both nicely versatile and available for 500€ used.
i love the LC series, if i could justify buying one i just might, but sadly i have enough gear for the moment.

the DSL401 is a great amp, aslong as you replace the sluggish stock speaker.

Epiphone Hummingbird
Epiphone Futura Custom Prophecy (Twin EMG)
Vox Valvetronix VT20+
Vox Wah
Boss MD-2
Danelectro Cool Cat Drive
Boss EQ