“22. It is clear that the question, at any rate now, is what is a 'reasonable sum on account of costs' … 23. What is a reasonable amount will depend on the circumstances, the chief of which is that there will, by definition, have been no detailed assessment and thus an element of uncertainty, the extent of which may differ widely from case to case as to what will be allowed on detailed assessment. Any sum will have to be an estimate. A reasonable sum would often be one that was an estimate of the likely level of recovery subject, as the costs claimants accept, to an appropriate margin to allow for error in the estimation. This can be done by taking the lowest figure in a likely range or making a deduction from a single estimated figure or perhaps from the lowest figure in the range if the range itself is not very broad.”
“(3) The litigant in person shall be allowed – (a) costs for the same categories of – (i) work; and (ii) disbursements, which would have been allowed if the work had been done or the disbursements had been made by a legal representative on the litigant in person’s behalf; (b) the payments reasonably made by the litigant in person for legal services relating to the conduct of the proceedings; and (c) the costs of obtaining expert assistance in assessing the costs claim. (4) The amount of costs to be allowed to the litigant in person for any item of work claimed will be – (a) where the litigant can prove financial loss, the amount that the litigant can prove to have been lost for time reasonably spent on doing the work; or (b) where the litigant cannot prove financial loss, an amount for the time reasonably spent on doing the work at the rate set out inPractice Direction 46 .” (a) costs for the same categories of – (i) work; and (ii) disbursements, which would have been allowed if the work had been done or the disbursements had been made by a legal representative on the litigant in person’s behalf; (b) the payments reasonably made by the litigant in person for legal services relating to the conduct of the proceedings; and (c) the costs of obtaining expert assistance in assessing the costs claim. (a) where the litigant can prove financial loss, the amount that the litigant can prove to have been lost for time reasonably spent on doing the work; or (b) where the litigant cannot prove financial loss, an amount for the time reasonably spent on doing the work at the rate set out inPractice Direction 46 .”