577
Cost of a 128KB computer with floppies in 1985
(sopuli.xyz)
This is a most excellent place for technology news and articles.
Two years later you could get an Amiga 500, with 512KB for £499. They were such a deal when they arrived. I bought a 20MB hard drive, an extra 512KB of RAM, a second floppy drive and a monitor. If I recall correctly that set me back around £1400.