We have a list just like the one you're in the process of doing Bath. It's an excel spreadsheet that lists all contents by room and value. I was also careful to over-estimate the value of things just a little and also didn't take into account whether or not I bought it on sale, I listed it at the cost I would pay without it being on sale. We are currently insured for $80,000 and I feel this is adequete for us at the moment, as we too live in quite a humble home, no flat screen tv's etc.

P.S Thanks for reminding me I need to update my list too