Okay, so 1/3rd of the monthly wage means 1/3rd of a month, meaning 26 hours of 4*40 hour weeks.
Assuming there's no other overhead an independent contractor needs to take care of in Italy (in the US the big one would be health insurance, but you live in a civilized country. On the other hand, your civilized country probably all takes reasonable paid vacation, and an independent contractor would probably want to charge enough to do the same. And there are other reasonable reasons contractor hourly rates tend to be higher than pro-rated full-time salaries, things included with a typical full-time job above the salary itself that a contractor has to pay for or spend time on themselves).
But okay, let's say 26 hours.
How many junior developers can take an idea, probably somewhat vague and poorly thought out, and turn it into something useful in 26 hours?
I'd say if they can, they probably ought not to be considered a 'junior' developer!
I meant it as 26 hours total, but I had my math completely wrong. 40 hours a week * 4 weeks * 1/3rd is 52.8. I had it halfed somehow. But anyway, yeah.
and somehow I STILL have my math slightly wrong. Can I not do arithmetic? 40 * 4 / 3 == 53.33.
Anyway, I guess there some projects that can be done well in 53 hours, but it's still not a huge amount of time. At "USD$450 should be fine as a third of a monthy salary!", that's approximately $9/hour. Really? Okay. If you can find someone willing to take $9/hour for 53 hours of work for a project that really can be done well in 53 hours.... I think my point stands.
It's 1/3rd the net monthly wage, i.e. probably less than 1/6th of the money you pay to have junior developer actually working for you for one month, once you factor in income tax, company tax, social insurance, sick time, vacation time and national holidays.
I wouldn't expect a junior to be able to manage the whole stack and get stuff on a server. Write an application probably, but it took me a few years before I could manage everything.
To be fair, I was probably exaggerating a bit when I said "trivial" but it is pretty straightforward and you can do all of it from inside Visual Studio:
Assuming there's no other overhead an independent contractor needs to take care of in Italy (in the US the big one would be health insurance, but you live in a civilized country. On the other hand, your civilized country probably all takes reasonable paid vacation, and an independent contractor would probably want to charge enough to do the same. And there are other reasonable reasons contractor hourly rates tend to be higher than pro-rated full-time salaries, things included with a typical full-time job above the salary itself that a contractor has to pay for or spend time on themselves).
But okay, let's say 26 hours.
How many junior developers can take an idea, probably somewhat vague and poorly thought out, and turn it into something useful in 26 hours?
I'd say if they can, they probably ought not to be considered a 'junior' developer!