Economical

Efficient in the use of scarce resources, especially financial resources.

"There is no hard and fast rule as to what size of [debt] funding programme warrants a dedicated Debt IR function. For companies that are infrequent issuers, it is typical and most economical for the treasurer and treasury team to manage the issuance process and also to act as the point of contact for investors..."

(Building a Debt IR function - the Treasurer's Wiki.)