computer repairs on site

I am in need of urgent computer repairs and are offering a project for someone to come to my premises based in Saltdean, Brighton and carry out both hardware and software repairs on Windows computers. The work preferably needs to be completed within 24 hours, so the successful freelancer will need to be available to start immediately. The repairs can either be done on site or removed to be repaired off site – whichever is more viable. The successful freelancer must have the technical skills and expertise to quickly assess the PCs and determine which repairs are needed and then be able to complete the work in a timely manner. They must be able to work autonomously and provide clear and concise updates on the progress of the repairs. They should also adhere to all safety measures and comply with all necessary regulations. The system used to function properly until I edited the registry then rebooted, it blue screened then asked me to repair Windows, after rebooting again the system got stuck in a loop where it will turn on, display a black screen then turn off again and repeat itself after a few seconds without displaying the logo on the screen. I attempted to clear the CMOS to try to resolve the issue but it did not help