Court fees are constantly changing, and saw a big hike last year. [news 5/7/2018: MoJ admits overcharging – but no money back! Most of the overcharging was due to overpriced fees on persona injury cases] Further guidance can be found here including advice on help with court fees. (see pages 14 – 17).
Although there might be differing views on using a solicitor, it is not a bad idea to get a lawyer to start things off for you, as they are familiar with the various forms and fees.
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After commencing proceedings though, you might like to consider cheaper options like DIY (being a Litigant in Person) in conjunction with a Direct Access Barrister, or using a McKenzie friend.