(Stamp Collecting): What is a good price, for high quality kiloware?

I used to have quite a large stamp collection when I was a kid, and have recently decided to get back in to it, as a future investment.

I am a little out of touch, so was wondering, how much is good kiloware worth now days?

What would you expect to pay, for 1 kilo of high quality kiloware?

By high quality, I mean with stamps in good condition, on single paper, cut neat and close to the stamp, from varied countries and years and face values, and that are genuinely unsorted and unpicked.

Thanks.