2400 W-hr/day @ 24VDC=100AH. 3 days=41% discharge from 2 banks of 410 AH (720 Ah). 82% of max repeated discharge of 50%. Re500; 300/500=60%, or ~71% of max repeated discharge of 85%. RE400; 300/400=75%, or 88% of max repeated discharge.
>>So the closest without going under (in performance) is the RE500x20 for 24VDC.
Cost of 8-L16S w/desulfators and exchange is ~$2,100 using existing connectors. 3 sets, with new connectors and price increase= ~ $6,600+ for roughly 21 years total or more. Bought in town 36 miles away and self transported (back breaking labor).
Cost of RE500 system w/ connectors and shpg. $9,251, and with 30% tax write-off for those with taxable income, $6,475.70.
Footprint for 8-L16S= ~2.5′ X ~2′ X ~18″ high. Footprint for 20 RE500s in 5 X 4 = 3.622′ X 2.264′ X 19″ high.