Ask HN: What metrics do you use when you buy stuff?

Taking inspiration from pg's RFS 2: New Paths Through Product Space, I'm working on a project called "Octopus". (octopus.org)

I'm looking to build a website where people can collaborate to build a resource of information on manufacturers, products and retailers. I'd like to help people to help each other and know all about the things we own and want, as well as the companies we buy from.

One of the things I'm thinking about, excluding the obvious like price and availability, are the metrics we use when we research and buy things. We're all unique in this respect, on the whole we like different things despite the fact we can also like the same things.

I like things that are robust and last a long-time. These can be from well known brands as well as relatively obscure ones. What metrics do you use when you buy stuff?