Mileage expenses and capital expenditure

I have been trying to find clarification for the following, without success, and wondered if anybody can help?

The question actually relates to travel costs when carrying out capital improvements on a buy-to-let property but could also apply to any capital asset.

When calculating the chargeable gain on disposal of an asset, enhancement expenditure is an allowable deduction, but do the travel costs borne by the taxpayer to carry out any enhancement work also count as part of the total costs of enhancement? For example, in the case of a residential letting, would the travel costs of travelling to collect building supplies and travelling to the property be allowable as part of the improvement costs? I have always been under the impression that they would make up part of the enhancement expenditure, but I can't actually find this detailed anywhere. If they are allowable, would the approved mileage rates be an acceptable way of calculating any allowable travel costs in relation to improvement expenditure, where a taxpayer uses their own vehicle?

Also on a similar thread, what about other travel costs that a taxpayer may incur in the initial stages of starting a property letting?

Incidental costs of acquiring or disposing of an asset are limited to:

• fees, commission or remuneration paid for professional services
• costs of transfer or conveyance
• costs of advertising to find a buyer or seller
• costs reasonably incurred in making any valuation or apportionment required for the purposes of the Capital Gains Tax computation.

Therefore, my interpretation of this is that travel costs in relation to acquiring or disposing an asset are not allowable (except in the case of chattels, where transport costs to the point of sale are allowable). So in the case of a buy-to-let property, the costs of travelling to an estate agent or solicitor to buy the property would not be allowable, but what about the travel costs associated with arranging finance on a property where the intention is to rent it out, are these travel costs associated with acquiring the property or an allowable revenue expense (costs of arranging finance) which can be claimed when the first letting commences?