Cain considers calling for clones of Symbia, but the real one will be here soon, so he might as well wait for her. Call it support for small local business.
He needs to decide what to have created to protect the house though. Four guards with gear, maybe a menacing Aura type curse for unauthorized visitors? Psychological warfare is good. Then a Barrier type Trap? They're simple things, if you reach the edge of the curse, you are returned to a specific point and disoriented. Either trapping the unaware, or keeping them out. It's not too hard to get around, or resist, but Cain plans to save the really good ones for the Guild Castle.
Yes, a Barrier trap on the windows would be good, have it move them back into the street. Simple, Safe and effective. Outright killing trespassers is frowned upon. Unless your Guilds are at war, in which case everything is fair game.