I recommending you have a look at:
http://www.rnha.co.uk/ - The Registered Nursing Home Association website. They have a directory of nursing homes and will probably be able to give you a lot of helpful information.
Nursing home fees will vary depending on the type and amount of care the inpatient needs so I suggest you do a lot of research first . I believe the funding arrangements are more generous in Scotland than in the rest of the country so I'm not sure you will be able to gain a meaninful comparison.
Also the Age Concern website (ageconcern.co.uk) has a lot of useful information & fact sheets you can download about all aspects of care for the elderly including any allowances they are entitled to. Is your mother getting an Attendance Allowance? It sounds as if she would be entitled to this, which would help towards her care home fees.