How do you buy / sell such heavy things like speakers over the web?

I'm planning to redo the system I've had for the last 15 years - selling what I have and buying used gear to replace. What I'm getting stuck on is how to sell/buy these ultra heavy items. My Krell amp weighs 110lbs - I can't even get it in it's box, much less get it to a UPS Store to send to a buyer. And how do you buy speakers remotely that weigh 150lbs or more each - get them shipped to Portland, Oregon, carried downstairs to the music room, out of their crates and tipped over to get the spikes on (and then stood back up)? Full service shipping. Where do you find outfits that do that? Any recommendations from those of you that have had the same challenge? - Thanks!