It's always risky to get involved in the first round especially when talking about the Serie A, but I think -0.5 is a good price for Bologna when they play host new promoted Crotone.
Roberto Donadoni is still in charge at Bologna and even though he hasn't got spectacular results at least he saved them from relegation last season. But this season might be a better one for them. I would say they got stronger with the arrival of Godfred Donsah from Cagliari, Ladislav Krejcí from Sparta Prague and Luca Rizzo from Sampdoria while no important player left. It's very important for Bologna to win direct games versus other relegation candidates and Crotone are one of them.
Crotone won promotion to the Serie A after ending up on second last season in the Serie B and even though they come with a winning mentality, their squad has changed a lot compared to last season. Many new players joined and their new manager Davide Nicola might not have time to build some kind of a team chemistry. It's always hard to play well with new players. This new manager doesn't has Serie A experience by the way, so I think it will be equally hard for the players but also for him as a coach.
So even if this is a risky bet, I will take this risk and back Bologna to win at home in the first match of the season.