I've tried installing this plugin called "sidebar login", it's a widget for a login form, this plugin allows users to login within the page they are on without living current page and seeing the wp login page.
So I've installed and activated the plugin but the sidebar login form is really massed up on this wordpress theme I am using, and I can tell you it's the theme's folt and not the plugin.
See attachment for details.
I always come across problems with wordpress so if I am satisfied with your work it's going to be a long term.
No up front payments.