The most expensive item I have purchased online was a used nintendo console that cost almost $200 if I remember it well. But one of the important cable was missing and luckily I had from the old one. I have made a lot of other purchases online from a different store but they never reached $100 each.
The most expensive purchase I have made online, was when I bought a laptop. It was delivered the next day and I have no complaints. Actually saved money as it was free shipping. That was a good futureshop investment.
The most expensive item I've ever gotten was the $550 I spent on my current laptop. And that was actually a good deal as it was priced for over $700. Staples was running a promotion at the time for computers and they had an extra online promotion of a free $50 coupon for any purchase over $400, or something along those lines. Other than computers, I don't really shop for many expensive items.