In Finland the house show thing isn't anyway near as big as in the States so I definitely come from a little different scenario BUT...
Private parties. Nothing beats good private parties. Nobody enters without an invitation even to a bachelor party or a local band scene birthday party jams, You know. The invitation has to come from (or look like coming from) a private network of like minded people executing their right to assemble and raise hell. And still not everybody at private parties are exactly friends of the organiser, are they? There are avecs, see, and the interested friends' friends that almost missed the occasion but made it after all, and the bad girls who go anywhere.
Church is not a good move, an
association for free exchange of music or something like that might perhaps work better.
At least in FInland it doesn't really cost You much to start a non-profit association that can collect tax-exempt fees (even in the tax-crazy Finland) from the members as long as it's used on what ever the association is promoting and offering for its members. Sure there is probably stuff to learn about legislation around that but who knows, it might be worth reading all that through and think about it.
Good private parties can be also organised at restaurants, mansions for rent, and warehouses if the money is used openly in a non-profit way. Just keep the checks safe in an orderly manner for the needed time afterwards should authorities be interested to check about the possible profits.
I've organised a few such parties for a Finnish pagan association, when I was a for example. I rented a nice historical house with the association monies, sent invitations (+avec), gave the authorities all the information they wanted, did all the needed paper work too, and welcomed the police to the outer hall way for a word when they showed at the door, showed them around a bit and all was dandy for them. The neighbors were alarmed by the torches, music, and stuff going on outside the house in animal costumes and suits but that was it.
