A starship's jump drive could be equipped with a black-box transmitter, that automatically broadcasts the current state of the mortgage as soon as a ship comes out of jump, and then, if payment is overdue, at periodic intervals. Or the ship's computer could include a hardware element that adds a carrier signal to any outgoing transmission, with this information. Overriding or tampering with this system would certainly be considered a crime, and a breach of the loan contract, resulting in forfeit of the ship and any previous payments.
Certainly, a ship could (and should, really, given the advanced state of technology) "know" whether payments on it are overdue, and could simply refuse to accept jump coordinates that put if farther away from the bank.
Banks might also demand a flight plan, with check-ins that can be communicated back to them, so ensure you're trustworthy.
I wonder too what's canon in terms of *where* payments are supposed to be made. Are you intended to return to the same system every month to make your payment? If so, that severely limits the range of a ship under mortgage. If you can make payments elsewhere (e.g., at any A or B starport, or in any system on an X-Boat route), then the farther you are away from the loan's "home", the longer it will take for the money you deposit to make it back to the loan - so does that imply you have to make payments that much earlier? Maybe this means a ship newly purchased has to stick close to the bank, until it can make an early payment, allowing it to travel farther away, and so on. If that were the case, then you might be able to pay a fee to move your loan to a new "home" that's closer to where you'll be flying.
Certainly, a ship could (and should, really, given the advanced state of technology) "know" whether payments on it are overdue, and could simply refuse to accept jump coordinates that put if farther away from the bank.
Banks might also demand a flight plan, with check-ins that can be communicated back to them, so ensure you're trustworthy.
I wonder too what's canon in terms of *where* payments are supposed to be made. Are you intended to return to the same system every month to make your payment? If so, that severely limits the range of a ship under mortgage. If you can make payments elsewhere (e.g., at any A or B starport, or in any system on an X-Boat route), then the farther you are away from the loan's "home", the longer it will take for the money you deposit to make it back to the loan - so does that imply you have to make payments that much earlier? Maybe this means a ship newly purchased has to stick close to the bank, until it can make an early payment, allowing it to travel farther away, and so on. If that were the case, then you might be able to pay a fee to move your loan to a new "home" that's closer to where you'll be flying.