From the description, I'm not getting much information about the project. However, by going through the standard practice, I believe you want to simulate X number of users concurrently on the application under test ( AUT) and want to measure the performance of some scenarios at the granularity level of transactions. My suggestion is, please provide some information about current Production Infrastructure, Test Infrastructure, Expected through and SLA which you are looking for.
Then I can propose a project plan, and expected deliveries and timeline.
Some of the standard deliveries, which I do for PT projects are as follows:
1. PT Plan
2. PT reports
3. RCA for issue
One more, if you will agree for JMeter, which is an open source tool then tool cost will be Zero.