Getting rid of those tree stones is a good start.
My neighbour got rid of his Ozito mower soon after buying one.
He uses an 18" Victa with Briggs 375 I sold to him cheap. I realise your mum can't do this.
I have an Ozito cordless drill and hand pruner. The drill is very good and the hand pruner works okay on thin branches up to 1cm thick. Got it on clearance for $36 down from $79. Found the drill on hard rubbish next door without a battery. I use the batteries from my Aldi impact driver!
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