Solar Generator with batteries on trailer - grid-tie or off-grid, 2.5kW

Description

We have three 2015/2016 SCT 20 Mobile Solar Generators with battery backup from DC SOLAR, wired up and ready to go. Great for cabin use or anywhere you have ground space available. Approximate cost of *parts* (unassembled), I'm told, is ,500. Links provided are closest I could find to actual equipment.
(Story: We bought three of these, thinking we could put them on our commercial roof for instant solar. A structural engineer said that was a non-starter on our 1905 concrete slab roof. So we need to sell these. All reasonable offers considered.)
Consists of:
2 - SMA Converters ( Sunny Island Off-grid Inverter Model # SI6048-US-10)
https://ressupply.com/inverters/sma-sunny-island-6048-us-10-inverter (51 ea.)
1 - Midnite Solar Classic 250 MPPT Charge Controller
http://www.midnitesolar.com/productPhoto.php?product_ID=258 (50)
2 - GNB Flooded Classic Platinum 24 cell 48 volt batteries Model M15 24-85-13B.
https://midatlanticindustrial.com/wp-content/uploads/2015/01/2414-GNB-Battery-Flooded-Classic-Platinum-Industrial-Batteries.pdf (00 ea)
10 - Solar Panels. The panels are either Talesun or Boviet Solar. Both are 250W/panel, so maximum 2.5kW per trailer, DC.
https://www.bovietsolarusa.com/wp-content/uploads/2017/01/Boviet_Datasheet_60Cell_Poly_250-270W_BVM6610P_BW.pdf (5 ea)
All equipment is assembled on a custom steel frame and bolted to:
1 - 6' X 17' Heavy duty car hauler trailer with steel bed, 4543KG/9995 lb. gross vehicle weight rating (GVWR) SC172 trailer, fitted with pintle hitch. (00)
If desired, we will unmount solar array from trailer, and remove trailer. Price without trailer, 00.