It is difficult to answer this question as a lot will depend on the type of dispute, the evidence available, the number of parties who are involved in the dispute and whether the parties are willing to negotiate.
Understandably, cost is a huge concern for those who are considering contesting a Will. Many clients do not have the funds to cover the cost of the legal work involved. Legal Aid is available if you have a very low income and few savings but few people are eligible.
Fortunately, there are a range of options for this type of work which opens up the availability of legal help to all.
Ways to fund the costs of legal work involved in contesting a Will include:
Contesting a Will on a ‘No win no fee’ damages based arrangement means that the cost of legal work is paid out of any damages that are recovered. The exact percentage of damages will depend on the risks involved with your individual case – typically, they will be 20 – 30%.
A straightforward no win no fee agreement means that if you win your case, the costs of the legal work, typically together with a success fee, are paid either out of the estate or by your opponent. If you lose, you pay nothing.
If you have not entered into a ‘no win no fee’ type agreement, solicitors and barristers will usually send you interim invoices – perhaps every month or two months. This usually makes the costs more manageable for clients.
Under this arrangement, the full costs of the legal work are paid at end of the case. This may be more convenient to clients who are awaiting funds from another source.
For some cases, a fixed fee can be quoted for some or all of the legal work. This means that even if the work takes longer than expected, you will not pay more than the fixed fee.
Usually if you win your case, your costs are paid either from the estate or by your opponent.
However, keep in mind that the Court has the discretion to make any order they see fit in relation to costs – and the conduct of the parties can influence their decision.
The Court might take into account, for example, that the Deceased caused the dispute because of their unreasonable behaviour, or that one party caused delays or difficulties in the case. Where someone has acted unreasonably in the proceedings, this will often be reflected in the order for costs (regardless of who won the case).
Also, if the circumstances were such that it was reasonable for there to be an investigation with regards to the Will, the parties may each bear their own costs.
The cases of Spiers v English , Costic v Chaplain  and Re Ritchie  confirm the above principles.
Remember that many cases do not go to court and can be solved through negotiation, with the help of an experienced lawyer.