A hosted builder gets a first version live quickly. But the monthly bill rises with usage, and many owners find they lack full control of their domain, data or code.
Begin with an inventory
Write down what the app really uses: the database, uploaded files, scheduled jobs, emails, secrets and the domain. Whatever is missed here turns into an outage later.
Practise the data move
Copy the database to its new home, compare row counts, spot-check some records, then repeat the whole thing. The live move ought to repeat something that has already worked.
Repair what turns up
A migration often reveals shortcuts, for example permissions that are only checked in the browser. Fix them as part of the move, while the code is open.
Switch at a quiet hour and keep a fallback
Move the domain at the quietest hour of the day and leave the old version untouched for a week. Should anything be wrong, going back takes minutes.