You need to give him root access on the server or make an account for him to use. Unless you need him creating more droplets, he won't need your DO login information.

If you don't want to give him access to your account details, we recently added the ability to transfer snapshots. So your developer could build up the server with their own account and the transfer the image to you when he's done. Check it out:

https://www.digitalocean.com/company/blog/easily-transfer-snapshots-between-accounts/

Create an account for him then let him SSH in and do what's necessary. You'll probably have to add him to the sudoers (see man visudo for info).

NEVER give out your root password.

Something else to consider before giving someone root access, is what kind of a website are you moving, and what's your relationship like with this person?

If I had an e-commerce store with customer information (names, addresses, phone numbers), then I would make sure that you met this individual at least a couple of times, and they live in the same area as you.

Heaven forbid this person steals or accidentally destroys your information, and lives in another country than you then you'll have little legal recourse.

If it's just a simple non-store website without customer information, then I wouldn't worry about it.