It's also important to change your password and admin username if someone helps you and needs admin username and your password to login to do the work. After all the work is finished, IMMEDIATELY change your password and admin username. Someone in their business may not be even if the man is trustworthy. Better to be safe than sorry!
I back my blogs using a plugin WP DB Backup up. If anything happens I can always restore my blog to the last settings. I use WP Security Scan plugin to scan my site and WordPress Firewall to block asks that are suspicious-looking to fix hacked wordpress site.
This is great news because it means that there's a community of users and developers that can further enhance the platform. However there's a big group there will always be people who will attempt to take down them.
This is quite handy plugin, protecting you against brute-force strikes that are password-crack. It keeps track of the IP address of every failed login attempt. You can configure the plugin go to these guys to disable login attempts for a selection of IP addresses when a certain number of failed attempts is reached.
You can also make a firewall that blocks hackers. The firewall prevents the hacker. You must also have updated version of Apache. Upgrade your PHP. It is essential that your system is always filled with upgrades.
Do not use wp_. That default is being eliminated by web hosting providers but if yours does not, fix wp_ to anything else but that.