I have homeowners insurance that covers my home and has a flat coverage for household items. For additional coverage you need to provide evidence of value. We have many items for which we don't have receipts and unlike jewelry, it isn't easy to find an appraiser for appliances, computers and the like. How can we provide the insurance company with evidence of value so we can get these items covered?
From my experience what they want is a receipt of when you've purchased the item. Otherwise, you can look up a similar item and provide a quote from a store on an item similar to the one you have with proof of existence of the item you claim to have (for example, a photograph of your laptop that shows its model and serial number, and a quote from Best-Buy, as an example, for a price on the same or similar model). That's how I had my camera insured once (when I still had a camera worth insuring...).
I've never needed to provide an evidence of value for my laptops or computers, by the way. But if it is an exceptionally expensive computer (for example, some crazy gamers' machine) - you'd better keep the receipts.
My agent had me spitball how much it would cost to replace all my stuff. There was a nice little worksheet to help me estimate, but basically it came off the top of my head. Your computer, appliances and other expensive items are still just off the shelf merchandise and therefore fall under that flat rate estimation.
Only if you have something that can be appraised do they need to know about it specifically. (Art, fine jewelry or antiques). Anything special and your agent / broker might very well have special paperwork describing exactly what you have to do to claim it's value.
Keeping your receipts is nice, but chances are slim that they will care. Furthermore, what you happened to have paid is NOT the same as the replacement cost, and likely won't calculate into what your insurance policy pays out to make you whole. Even super expensive consumer goods like televisions have big price swings in just a couple of years.
Since I was in the ballpark for their estimation, the agent took my estimate. Had I asked for more coverage, it would have cost more. To answer your question, my agent doesn't care about exactly what I had, just how much I want to replace all of it at once. In the event of a disaster they will (supposedly) cut me a check for how much I asked for. (Receipts aren't going to hurt to have, but where you keep your receipts is probably going to suffer the same fate as whatever happens to the items they represent, right?)
Therefore it is important to once in a while evaluate your stuff and tell your agent how much coverage you need. For special items that are rare or exceptional, you need to have your appraisals updated and a rider on the policy to cover those items too.
I think Clark Howard suggested it, but once a year (on your birthday or at Christmas) make a video of all the valuable stuff in your house, talk about it a little bit and put that video somewhere safe in case your house burns down. (YouTube, a DVD at a relative's house) Then, take the time to contact your insurance agent and make sure your coverage is appropriate for what you own.
YIKES I have State Farm Insurance, and here is worksheet I found on their site. http://learningcenter.statefarm.com/residence/insurance-2/creating-a-home-inventory/ I did not have this from my agent, and it is crazily detailed. I stand by my original answer. I guess your true answer comes from your agent.