She needs to use that money wisely.
look for local properties to buy though with £125k and being a TA on benefits this might not be the best use of the funds as losing the house later due to not being able to pay the mortgage/upkeep without also trying to improve job situation would be likely
mapping out a budget of where to put this money would someone experienced, a financial advisor would be money well spent.
personally I’d look at in no particular order -
retrain or upskill to get better pay. This could be a set of day courses, open university degree, discussing with her employer about further in work qualifications to get a better paid position. Use the entire fund for 3/4years at university to gain a quality degree. That money would be enough get a degree and QTS for example if she wished to stay in the education sector of course she needs to be academically able to do so.
use it as a buffer to switch jobs to something that pays more. She’ll have the funds to get good childcare whilst doing a new job. The money would be giving her that much needed hand up to cover upfront childcare costs that others in her situation struggle with.
put a chunk of it into a private pension as this alongside her existing LGPS won’t be take into account by DWP as it is a pension. (Double check though)
open a savings account and drop 6k in as an emergency fund as this is what the savings limit is before UC taper starts.
pay off any debts and get bills where possible and appropriate a month or so ahead and keep them ahead.
replace anything that needs to be replaced. NEED not want OR things that would improve her life eg a dishwasher or tumble dryer.
my first big chunk of backdated benefits (I was a carer to a disabled child) I bought a dishwasher, larger fridge and tumble dryer. this improved our lives massively as I was able to shop for food less often - I only had a camping fridge- actually deal with bed wetting without it taking all day and not spend hours cleaning every day. This made it possible for me to retrain in my spare time as I finally had some and then enter the workforce as DC grew older.
if I had 125k right now my first stop would be to pay off any debts owed and budget accordingly for a second degree, my outgoings and rent for the 4years I’d need and the degree fees as well as replace the clutch/gearbox on my car as it’s fab, cheap to run and insure. I know the area I’m currently training in is short of worker and there’s plenty of jobs.
this is what she needs to do but appropriate to her situation . Big picture but also small life improvements that would really improve things and not spaff it up the wall on crap. She should also keep receipts for everything so she can prove it’s not wasted.