Anthony

it works out expensive in my view  rather buy the royal batteries 105ah at R1500 or so 
R6000 for 48v 100ah   vs R5000  
and simpler wiring and less monitoring of the batteries 

There are UPSes that use small lead acid batteries in long strings (96V I think) and do well enough, but for backup purposes, not for daily cycling. So in principle doable, but the cycle life is not going to be that great. 200-400 cycles according to some random specsheet I googled into.
I think the biggest issue is going to be when one cell goes short circuit and that string starts to pull current from the other 7 (plus charge current), cooking the rest of the cells until one of them blows up like a balloon and then potentially explodes.
Odds of that happening is 8 times greater than with a single string...
Severity of things going bad... also much worse.
Risk = likelihood x severity.
I agree with @scrarfussi, if you're going to cheap out, cheap out on the Royals. Though of course... you may not be able to find stock of those 🙂
Or.... design a RAIB... random array of inexpensive batteries 😛