I could only see a couple of the mattresses when I bid.  The other mattresses were covered with blankets it looked like other furniture.  I like to buy junky looking unit cause normally I do not loose money as they are cheap.  I thought there might be some good scrap in the unit there was not.

I once bought a unit for $50 that when I returned the personals I was told the guy had died 9 years ago and a friend was paying $205 a month to keep his stuff.  Well it was really dirty and had a lot of junk in it. The friend had paid $22,140 over 9 years. I made a few hundred mainly off scrap there were 2 Honda 750 engines in the unit one frozen up.  Lots of other scrap.  Most of the stuff was junk.  I can not explain it but I see it all the time.

Thrift stores around here do not buy stuff they take donations.  If you do not have a good storage area avoid large items like couches or mattresses.  Sell as fast as you can storage is expensive I would rather give my mediocre stuff to goodwill then pay to store it and I have a big garage 28X33 feet and 2 stories. 
I have rented trucks before and they are expensive (last time between rental and fuel it was $200)  but sometimes you have things to get rid of.  In the past I rented a truck if I had a lot of mattresses.  I now have a trailer and it is paying for itself fast. All my mattresses go to the dump.

Trash is broken toys, paperwork, magazines, sex toys, pissed on mattresses, couches with holes burned in them, food that is 10 years expired (ever seen black ketchup?), ripped clothes, clothes that were packed dirty and have mildewed for years (I find a lot of this), dressers with drawers missing, porn, empty DVD boxes, empty CD cases, VCR tapes with no cover on them or home recorded, broken or chipped dishes, underwear, cassette tapes, worn out tires, scrap lumber, pianos that have sat in the barn for 20 years before being moved into storage, 8 track tapes (most are no good).  That is all stuff that goes to the dump.  Unsoiled clothes mostly go to goodwill I only keep the good stuff like new with labels or leathers and furs.  Furniture that is still usable can be sold on craigslist but most of it has to be sold cheap to get anyone interested. I give a lot of usable but ugly furniture away. It all boils down to is it worth messing with and do I have room to store it while trying to sell it.  Most cheap household good are not worth messing with unless you have a retail outlet or do flea markets all the time. Most dishes that say made in China go to goodwill.  A lot of the electronics you find do not work.  Unheated moist storage is hard on electronics.  Right now all CRT TVs are worthless even if they work.  I strip the copper out of them and then take them to goodwill who have a deal with the county to recycle e waste. They take them working or not.  Most VCR players are not worth messing with they get scrapped for copper content.  Most CD players are only worth a few dollars if they work.  I figure 90 to 95% of the stuff I get in a typical unit is thrown out or donated.  I know some of it could be sold for modest amounts but I have not enough time or room to mess with it.  I am the kind who likes to buy units that are messy and dirty looking because they normally do not go real high and it is easy to get your money back.  My best unit was a 10X20 full of trash that I bought for $50.  Found over $4000 cash in it but I hauled about 4000 pounds to the dump.  I buy $1 units as long as they are not all mattresses and couches. I assume all stuffed furniture is no good when I bid. 

I think the neighborhood is most important. Buy units in a ghetto and you get gang banger stuff. Buy them in an upscale area with no low income housing and get better stuff.

Well here in WA it would be considered stealing since the contents belong to the renter until sold at auction. Not to say it does not happen but I suspect it more likely the unit will be posed as in the best stuff will be showing.

I much prefer the whole unit much better chance of getting something good and you do not end up with half of something as often.