I would suppose that all the assets are pooled when two churches merge, but it is possible that some would be offered back to the donors. You might have some duplication of sound systems or food service, and you probably are merging because both churches have lost members. You may be planning to sell one of the church properties.
It is possible to have two churches use the same building but keep separate accounts. You could have the property owned by one and rented by the other, or it could be jointly owned with expenses shared.
The real question might be what to do if one property is sold and there is surplus cash. Some churches might decide to give to a charity or two. Or the property might sometimes be sold below market value to another church that needs a home.
It is rare that congregations need to merge but when they do it is an orderly process for the benefit of the members. Usually in a merger one congregation has suffered the loss of use of their meeting place. One case I know was when a Pentecostal congregation suffered an arson fire. An atheist threw a molotov cocktail into one of their windows and the building was gutted.
We offered them the use of our facilities until their insurance paid their claim and their contractors finished work. As it turns out, some of our members had distant relatives in the other congregation. They found other family members and the congregation grew remarkably.
The other congregation rebuilt their fire damaged structures and resumed meetings, we had increased membership and so did they. We're still on the best of terms.
Even as we face the bitterest of persecution, the Lord's work will always prosper.
Rocmike aka American Patriot is starting today's posting marathon off with Bernard McCaunaghy. We are in store of hours and hours and hours of aliases repeating the same thing over and over and going to old questions and answers no one has been on in a long time. Rocmike do you have your aliases chosen for today?