As it’s going to be used for work purposes, it needs to be a fairly ‘current’ ‘phone. Refurb deals are ok, but it might be at least part-funded by her work*. It needs to come from a reputable supplier, so Samsung UK, John Lewis, Carphone Warehouse etc. The A13 has a dual SIM feature, which would negate the use of a separate ‘phone. Can you turn one SIM ‘off’ if you’re not working, say at weekends/holidays etc? Is it easy to switch between SIMs?
*There are also security/GDPR issues which mean a Samsung ‘phone is apparently better than some other brands (the IT service the organisation uses recommends Samsung over other brands). I know bugger all about all that kind of stuff though.