I've been making my own juice since i started vaping, about 10yrs ago. I used to get 72-100mg/ml nic, that stopped being available (i get it, its dangerous), now I only have access to 20mg/ml nicshots which are 5 bucks a pop out here. So, what I'm reading into this is that as far as equipment itself, I can pretty much forget about new rtas/mods? all I can find in shops is pretty much new old stock, and only the stuff that didnt sell that well.
B&Mshops and manufacturers dont like to sell mods with rtas on them. They would much prefer you use coil cartridges as they make a lot more money long term.
Often the mods are only available as kits with a useless coil cartridge atty. i generally buy the mod i want and if I can’t do it i just buy the kit and leave the atty in the box (which I save). Online ordering is usually the only way to get stuff. I dont know what the rules are in Portugal.
The 100mg\ml base is only really dangerous if a baby drinks it. It’s already cut down 1/10, pure nic is a tiny bit heavier than water. So 1000+mg/cu. The actually pure stuff is a white powder and IS really dangerous. You gotta wear a bunny suit to handle it. It usually comes in drums.
If 20mg/ml is all you can get its all you can get though. Could be an EU thing. If you can order EU wide though you should be OK.
The best EU stuff used to be German, with the occasional bright spot coming out of Russia. The latter doesn’t happen much now of course. Europeans as a rule tend to be much better with multiple languages, so you may get lucky there. If not there i always machine translation. AliExpress is also a good bet, with the mods being sold as battery powered soldering irons. Theres this cute little soldering tip that fits in a 510. They even work pretty well.
Maybe try Ireland. Britain has a lively market but they're not EU anymore. There may be trade though.