You may benefit from giving them a space to battle. If you live in the suburbs of country, establish that they’re not allowed to battle indoors and reinforce this with positive reinforcement (by giving them treats whenever they keep themselves from fighting inside). Then, give them their own battlefield in your yard and be sure to oversee their battles. If you can, obtain a psychic pokémon that can separate them if they get too rowdy.
If you live in the city, however, that psychic pokémon I’ve just suggested may be essential to you, especially if it can learn Disable and possesses some level of precognitive skill. You see, a pokémon that possesses these exact characteristics can either see a fight and stop it before it starts or, if the fight breaks out anyway, use its telekinetic abilities to keep them separate until they cool off. Hence, a psychic-type can serve as an ideal mediator for fighting-types.
After that, of course, you will want to establish a safe place for the two to fight—a park or the courts at your nearest pokémon center, for example. Establish a routine in which you’ll allow them to battle so they’ll know they can regularly spar and fight as aggressively as they’d like without destroying your property.
In other words, the best way to establish boundaries is by offering alternatives and being consistent with your alternatives. Once you teach your hawlucha and pignite that there is quite literally a time and place for everything—including battles—they’ll be less likely to demolish your home and more likely to look forward to this special something every day.
But yes, consider getting a psychic-type too.