I always had a problem with Chapter Houses of covenants. It just doesn't make much sense to allow a Chapter House, it's just another covenant with alleigiance to an existing covenant so any other covenant would be better off recognizing it as a covenant rather than a chapter house. And on the other side, how do you differentiate between a chapter house and a magus deciding to live a while in the city or the wilderness? But I digress.
The answer is obviously dependant on the tribunal, and your saga. In tribunals that regulate the formation of covenants, and I think most do, it is certainly required to gain Tribunal permission to found a covenant. I believe the Rhine tribunal book detailed requirements that are probably a good candidate for being default - you have to convince enough existing covenants to support your desire [and none to veto it, oops].
I think a reasonable peripheral rule would be to disallow more than one magus to reside together except within an established covenant or for a limited time (I think a Season will do), or to make a covenant between them except to a recognized covenant.
You can't forbid lone magi, as that will alienate the eremites (lone hermits) which are highly respected. So lone magi must be allowed to roam the tribunal, or at least set up camp somewhere.
You'd want to forbid people just setting up camp somewhere, as you want to control the covenants and their chapter houses, so you forbid two or more magi. But you need to send excursions and whatnot, and don't want to forbid visitors and so on, so you give a period that's enough for an expedition or visitation - a Season - but not enough to become a long-term thing - a single lab season of work isn't desirable enough to create an incentive to flaunt anti-covenant laws.
The decision to recognize a new covenant would be made in Tribunal, following the local peripheral code and customs. Being accepted will probably require a long period of solisitation, visiting other covenants and bargaining with them, and so on. The Tribunal meeting will be a regular one, unless you REALLY bribed some powerful covenants.
Unrecognized covenants will be violating the peripheral code, though not the Oath, so may face punishments in raw vis and service to the tribunal. The Redcaps are under no obligation to serve them, although they may choose to do so. Since they cannot strike a covenant between them, they cannot share communal resources such as a library or raw vis - so if one magus steals the common coffers he isn't guilty of any Hermetic crime (though you may still declare Wizard's War or Certamen on the matter). They could not register raw vis sources in the tribunal's records, so have no claim to such sources unless they are somehow within someone's sanctum or something like that - harvesting the raw vis from the source will not be considered depriving the covenant or its magi from magic, since the source and the unharvested raw vis isn't theirs, it's just out there for anyone to grab. They may not be able to attend Tribunal, as foreign magi may be denied this right (claiming they can attend their own home Tribunal). Even if they can't attend tribunal, they can appear before it and make claims and accusations, and defend themselves - they cannot, however, vote.