Please remove all trash and do not leave any furniture, as the trash hauler charges extra for mattresses and furniture, which would be charged back to her if left by dumpster.  

I have a 1bd/2bth condo in the mountains with a king sized mattress in the bedroom and a queen sized sleeper sofa in the living room.

Some of the more bizarre: A window for an old Jeep Cherokee was left behind (found behind a door).A new, crated shower stall was once left in my parking lot (there was some weird story behind it like the tenant had intended to use for an in-laws remodel).Too many artificial x-mas trees to count.A machete (under a mattress)On a turnover, I once vacuumed under a refrigerator of a condo and just kept sucking up dried up dead small birds the tenant's cat had hunted and left behind.

I've seen garbage (mattresses, furniture, etc) piled up around the dumpster. 

Also, by "better for the neighborhood" I mean that the past tenants had unruly kids (jumping the fence to swim in the neighbors pool) and left large piles of garbage in front of the house, mattresses chairs etc.I hope this works out for them.

With the economy falling apart, what would you do with it, put it under the mattress?

If you prefer to hold "cash" in whatever denomination in a safety deposit box, home safe, in a Mason jar buried in the backyard or under your mattress...several companies will sell you currency from a number of countries.

. $99 mattresses and Goodwill furnishings will not cut it. there's a lot that goes into it.

Most of my tenants just lay a mattress on the floor to sleep and they do stupid stuff like wash their clothes in the bath tub instead of the local laundry mat so there’s really no point in offering amenities or wasting profits on nice finishes  to my clientele.

If you think of it as a savings vehicle you need to know that you'll probably do better taking your life insurance premiums and stacking it under your mattress.