Merces locationis

(a) Merces uera et certa

The second essential element on which agreement had to be reached before a contract of locatio conductio could be said to have come into existence was the rent {merces locationis): "...

Obviously the locatio could not be made donationis causa^[1804] and thus, for instance, a conductio nummo uno was invalid.^[1805] There was no verum pretium. As to the "certainty of price" requirement, the same problem cases were discussed as in sale. What if I let my house for "quanti Titius aestimaverit" or what if no reward is fixed at the time of the conclusion of the contract, on the understanding that such agreement may be reached at a later stage? Gaius leaves these questions open,^[1806] but Justinian says "non proprie locatio et conductio contrahi intellegitur".^{[1807] [1808] And as to the question of equality in exchange, we can refer to Paulus D. 19, 2, 22, 3, this notorious epitome of individualism in the domain of Roman private law:}

"Quemadmodum in emendo ct vendendo naturaliter concessum est quod pluris sit minoris emere, quod minoris sit pluris vendere et ita invicem se circumscribere, ita in locationibus quoque et conductionibus iuris est."⁴¹

(b) Pecunia numerata?

Somewhat more complex is the situation with regard to the first of the above-mentioned requirements, namely that the merces had to consist in pecunia numerata.

There is considerable dispute whether classical law recognized further exceptions to the pecunia numerata requirement. Two smallholders own one ox each. In order to pool their assets, they agree that each of them may in turn use both oxen for a period often days.^[1813] Locatio conductio? Two persons who do not get on with each other own a farm in common. They agree that each of them will in turn hire the other's share for a year at a time with the effect that they would be in a position, in alternate years, to use and draw the profits of the whole farm. After he has had the farm for one year, the one party sends his cattle onto the field, with the result that the prospects of the following year's cron are ruined. Can the other party avail himself of the actio conduct!?^[1814] In the first example, the granting of an actio in factum was considered, in the second one (involving co-owners) the actio communi dividundo. Others seem to have argued that the actions arising from locatio conductio could be applied.^[1815] But ultimately, still in classical law,^[1816] the view came to prevail that locatio conductio required a merces in money.^[1817] This was Justinian's view too, and use-exchange transactions came to be accommodated as innominate contracts.

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