If your next admin is going to be someone you don't know personally, you may want to agree on a code that you can give him (a word or phrase, a numerical code or a chess move) that you can occasionally ask him for authentication. Tell him ofc to delete the DM in which you give him that code.
Also, change your password every 3 or 6 months to stay ahead of brute force attacks (i.e. someone using a program to spam passwords on your login page until one works), and ask your admin to do the same.
If you have the possibility to do so, you may want to set up your website so that, after like 3 failed password attempts, the user has to wait 15 minutes before he can try again.
And finally, I myself store my passwords on a USB-stick, so that I can keep them offline, and still have them at hand when I need to.
I'm happy to be of help of course, and even gladder to find you back in business. Welcome back!!
Kindly,
Arikania