Plugin for client file uploads?

Hi,
I’m looking for a plugin (or some similar solution) that will allow clients to upload files (multiple images or documents) to my hosting account through my website. I’m not sure what other features to consider in terms of registration.

I have Googled around and found various options, some too technical for my understanding, some specifically for individual images with added tools. None quite right though. At the this stage I just need a basic but secure/ stable front end upload tool.

Any recommendations are appreciated, thanks.