Trouble recreating my site locally My online site gives "server encountered an unexpected error" and the shared hosting site (1and1) gives no log access. So I am trying to recreate my site at home.
I started with a clean install of D8.5, and installed my theme, which works. Then I replaced the database with the SQL dump I made on the host when my site was working. I also copied the modules directory to my site, and carefully copied sites/default/files, but just my image files.
But now my local version wants to reinstall from the start. How do I manage to recreate my site properly?
I could never use backup/restore on my host site--it had an error and would not activate.
So, without knowing more about your production and dev environments, it's hard to say. 

Most people would probably advocate moving your codebase with GIT, rather than manually as FTP programs will usually not move files prefixed like your .htaccess file (which maybe causing your whitescreen). If you're going the manual route, I would rsync a copy of your production sites folder, zip it, and the move it to your local computer, install drupal from scratch, then move your files over, set up the db and settings.php for your local environment, run update.php, and profit.