County and municipal agencies in Polk County, Missouri sell surplus through online auction sites like GovDeals and Public Surplus. BidProwl tracks all of them in one place: 19 live lots right now. Register on the platform hosting the lot you want; most items are local pickup only.
The usual mix is retired fleet vehicles and police cruisers, public works equipment, school district electronics and furniture, and unclaimed or seized property. Inventory refreshes daily as agencies list new surplus.
19 live auctions across Polk County right now.

non working
Non-working speakers, salvage condition
Dimensions - Overall - Length: 11' 1" - Width: 62" - Height: 101" Features - Ball hitch: 2" Tires - Size: ST205/75R15 Notes - Transport Dimensions: 15...

condition unknown
Salvage condition, status unknown
Dimensions - Overall - Length: 11' 1" - Width: 62" - Height: 101" Features - Ball hitch: 2" Tires - Size: ST205/75R15 Notes - Transport Dimensions: 15...

1 EV branded speaker working condition unknown.
Working condition unknown, salvage listed

condition unknown
Salvage/Damaged condition, purpose unknown

working condition unknown
Working condition unknown, labeled salvage/damaged

Condttion unknown.
Salvage/Damaged, condition unknown

Scrap Air Handler, for parts only

This is a serving line cooling table that was working when taken out of service. The dimensions are 102 3/4in long,26 1/2in wide, 34 1/2in tall. 110v...
Salvage condition, status after storage unknown

Condition non working
Speakers non-working, salvage condition

condition unknown. No speakers.
Salvage condition, no speakers, unknown functionality

2-MA 112 pro air purifier
Salvage condition, for parts only

Working condition unknown
Working condition unknown, salvage item

working condition unknown
Salvage item, working condition unknown

working when taken out of service. 72 1/2in long, 22 1/2in wide, 37in tall. 240v
Salvage/damaged, working condition unverified

condition unknown
Salvage/Damaged, condition unknown

Used 3d Printer non-working.
Non-working 3D printer, salvage condition