In the game “Mario & Luigi: Brothership,” there is no specific mention of a maximum coin limit that Mario and Luigi can carry. The game does include challenges related to collecting coins, such as the “Coin Enthusiast” and “Coin Collector” challenges, but it does not specify a maximum amount of coins that can be carried.

However, in other Mario games, the maximum amount of coins that can be held by Mario is typically 9999, as seen in games like “Super Mario Bros.” and “Super Mario Bros. Deluxe.” This information does not apply directly to “Mario & Luigi: Brothership,” but it gives an idea of how coin limits are generally handled in the Mario series.