ms project - rent a tool for half day

[nati2009]

hi

i have many tools that i rent at cost per day when i need them just for 0.5 day  

for example i need a bomag for 0.5 day but the cost for rent bomag is 300usd per day 

so when i enter resources for a task in the ms project its calculte it as  0.5 (day ) *300 (cost ) usd so its 150 usd , even that i set the resources to 300usd/day at the resources sheet 

how can i set at ms project that if i use the bomag resources even if it for 0.5 day its will cost me like full day ? 

i cant do it like " cost per use " beacuse i have many tools like that and i change the work time a lot 

[#2]

@nati2009,

Even though at resource rate may be set for cost per day or cost per hour, internally Project calculates all time related data to the nearest minute. For example, a resource rate of $1/hr will show a cost of $.016 (rounded to $0.02) for a task with a duration of 1 minute.

If you don't want to use the "cost per use" then I suggest you set up your tool costs as cost type resources. In this example the bomag is a cost type resource so no rate is given. When the bomag is assigned to a task,  the rate is set in the Cost column of the Assign Resource window. This cost will be fixed regardless of the task's duration.

Hope this helps.

John