I have on file over 15,000 images taken over the past 12 years. I have them stored on three external drives - all sync'd. That is triple redundancy.
I do have a laptop with two HDDs (one in the optical Ultrabay) totalling 570GB, but that is only for field collection work. Laptops are not designed to be used as servers (a server runs normally 24/7.)
Looking ahead, the next step will probably be to use a NAS.
For now, suggest using Rottie's external USB and grow from there. Also, it is somewhat of a waste of time to try and compress .JPG images. They are already that way.