How much to charge

Don’t charge them anything.

It’ll take less than 5 minutes to set up, and email them, Admin account credentials.

Apart from that, you’re going to still be billing them for the hosting AND you’ll get the work when they mess things up (and they will - they wont mean to but they will).

So keep them on-side and keep on billing them - for the sake of 5 minutes work, think of the long game.

The OP seems to have lost interest in this topic months ago, so there seems little point in reviving it again now.

Thanks to all those who contributed. Thread closed.