storing uploaded photos and documents - filesystem vs database blob
While there are exceptions to everything, the general case is that storing images in the file system is your best bet. You can easily provide caching services to the images, you don't need to worry about additional code to handle image processing, and you can easily do maintenance on the images if needed through standard image editing methods.
It sounds like your business model fits nicely into this scenario.
My specific situation
Property management web site where users can upload photos and lease documents.  For every apartment unit, there might be 4 photos, so there won't be an overwhelming number of photo in the system.  
For photos, there will be thumbnails of each.
My question
My #1 priority is performance.  For the end user, I want to load pages and show the image as fast as possible.  
Should I store the images inside the database, or file system, or doesn't matter?  Do I need to be caching anything?
Thanks in advance!