I actually worked on a small project that involved deploying headless desktop-based Debian servers to locations all over the continental US.
We'd fed-ex the boxes, and most of the time, they'd show up with a hard drive detached, or worse (one fedex ground shipment from CA to FL knocked the RAM right out of the slots on one box). What was worse, we didn't have any technical expertise on site to speak of, so even simple problems were hard to diagnose.
The ASUS motherboards we were using happened to have serial ports, and the BIOS also happened to natively support pumping text-mode input/output over said serial interface -- so you could edit BIOS settings, tweak bootloader settings, put the machine in single user mode and fsck the whole disk, etc. etc. all over serial.
We experimented with plugging these things into serial-over-ip devices; specifically, one like this one -- although I think we paid about $60 each. Results were mixed. For one, it was pretty painful getting things operating at a reasonable serial bitrate (especially for curses-esque interfaces like the BIOS settings interface -- characters were getting lost), and making them reliably accessible over IP wasn't easy either. You could configure these things to "phone home" when they were powered on, but the configuration interface and documentation was pretty bad.
If I recall correctly, KVM over IP devices were a bit more pricey.
So, long story short, when it comes to low-cost remote server management, in my experience, there's something of a lack of quality offerings.