Which desktop mac do you recommend to buy

Personally, regardless of model, with Adobe apps, get a machine with at least 32GB of RAM. When I was using my late 2013 27" iMac with 32GB of RAM with Adobe LR and PS, they would quickly gobble up over half of that in a short session. And that was a few years ago. I hate to think what they gobble up now.

Internal storage for is very expensive and I would get 512 GB and then you can get 1 or 2 TB (or more) high speed external Thunderbolt SSD which will be cheaper than what you would pay for 2TB of internal storage. Use the internal drive for apps and work in progress if the external is not sufficiently fast enough.

Beyond that, my rule of thumb has been get the highest performance machine that will comfortably fit your budget.

I wanted extra TB ports so it was a choice between the Mini Pro and the Studio. I got the studio so I could also have some ports on the front side to use. I got the 512GB with the 32GB ram and works great. I feel this will also future proof for use. I also got a LG 5K 27" display which also has extra ports on the back so now I do not need a hub.

First, it's a budget question.

I don't see a urge to go for a M3. M2 will do the trick and for a long time.

If you use hungry apps, aim for more RAM, faster processor, and if you need space, aim for a 2 TB internal SSD.

I do lots of audio work, some video, and my mini 2018 has 32GB ram, 2 TB and I'm probably good to go for another couples of years. Not giving you a receipe, just sharing my own experience.

If the Apple Store in Finland has a Certified Refurbished section, and you can find one of the machines you want there, that might be one way to save money.

Like tbirdvet, I wanted more ports than the base M2 Mini had. I was looking at the M2 Pro Mac mini, the M2 Max Mac Studio, and the Certified Refurbished M1 Max Mac Studio. I ended up going with the latter, and attaching a credit-card-sized 4 TB USB-C SSD. The front-panel USB-C ports and SDXC card slot have been very useful.

Where are you ?

Refurbished may depend on location, but also its content vary constantly. You may not see a model you want one day, then a few days later it will be there.

Refurbished is a good option - same as new when purchased from Apple.

I'm seeing a lot of Wifi & Bluetooth problems in the new Minis, so investigate that before considering further.