22 is too low for June!!! Okay I'm from Sardinia and there it can get nasty (yesterday there were 41 degrees in my village!), but still...
Stazione Termini is probably one of the sketchiest places in Rome!
Anyway, as you seem to travel a lot, I will link you an article of mine (not everyone of them, you can surely check them :) ) so that you can budget up while you go from place to place https://steemit.com/travel/@borderedge/how-to-find-the-cheapest-flights-from-anywhere
Oh, sorry! Must have gotten lost in my reply list. 22 is low, but you get used to it fast. Always easier to put more clothes on than having to heal with hot weather. At least that's what I think. Sardinia is super hot, I can imagine. I experienced a bit of that kind of climate when I lived in Malta for almost a year.
Termini is dodgy, no doubt about it. But the place was nice and the few hundred meters to the station weren't that much of a hassle for us to cross. Plus, I am no stranger to sketchy places. I am just checking your posts and sending you some heavy HF19 upvotes... :) All the best!