You can diy Richard using the online tool at the site of The Office Of The Public Guardian. I did this a couple of years back and the registration fee has since fallen a little to £82 for each LPA. That would be £164 if you opt for both types of LPA which are "property and financial affairs" and "health and welfare". I would really recommend that you apply for both, I did not and when push came to shove I regretted not having "health and welfare". I found that outfits operating as local councils and the NHS can deploy women with very sharp elbows when any decision could impact on them financially. There is no guarantee but I tend to think on my experience that faced with both LPAs they might afford you and your mum a little more thought and respect.
The fees might be reduced or waived altogether depending on your mum's circumstances. The place to start is here.
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