Changing servers, what happens to the guild?

[MistakeNot]

In order to transfer servers, characters cannot be in any Free Company, and cannot own any housing.

With one, or rather two, exceptions.

If you transfer to a New World, or from a Congested World to a Preferred World, then you will get reimbursement for any housing you have.
( https://eu.finalfantasyxiv.com/lodes...ion_balancing/ )

But you still cannot be a member of any Free Company when you transfer, so the question of reimbursement of any FC house is moot.

[Shibi]

But you still cannot be a member of any Free Company when you transfer, so the question of reimbursement of any FC house is moot.

yes, absolutely and have my like please.

OP says they bought an apartment though, so they might be doing the 3 people FC as tenants, not as in a house. In that case, the apartment owner will get $1 million gil for transferring to to a new world (currently Materia has this status) or from congested to preferred without abandoning, as you also correctly point out.