Karel but here in Italy friends tell me to avoid them
Follow your friends advice
If you write the full address we can check exactly what's available and what's best there.
Karel Also considering buying my own modem rather than getting it included with the subscription. Would that be worth it? In addition I work freelance with p.IVA so I could detract costs
You do you, "business" connections of this kind are identical to consumer connections, just with the invoice directed to your company/p.iva.
Karel Our house is not very close to any of the black lines
Then you shouldn't be covered by BUL, perhaps Piano Italia in the future or a private company at some point. With the full address we can give you more info.
Karel So I was thinking to end the contract in September (through PEC) and start a new contract straight away on the new address? Is that a bad idea?
Unless you need to keep the same land line number, I suggest you to go for a totally new line/contract and then you cancel the old one. By far the easiest and most trouble-free way.