2nd interview presentation - personal challenges

Hi I have to do a presentation on monday morning for a job as a Procurement & Contracts Officer for a public sector company involved in Education. The job is to create and administor all procurement contracts and frameworks. I have 4 years experiance working in purchasing for an NHS trust. I had a telephone interview with this company on friday and was told I had got through to the next level but would not be progressed further untill after christmas due to staffing/holiday issues. However I was called again yesterday to be told they want to see me on monday morning for a face to face interview including a 5 tp 10 min presentation on:

What personal challenges do you believe will arise for you within this role and how will you overcome these?
And
How do you intend to build your credibility both within the Procurement team and the wider College?

For each question, choose three skills you have and then give a detail example of how you've put that skill into practice before

eg: How do you intend to build credibility:

1. I will build relationships eg:at my previous job I....
2. I won't over promise and I will deliver on my promises eg: at my previous job I was asked to.....but I knew it couldn't be done and was honest and upfront. I did say what I could do and delivered on that
3. I will ensure the procurement system is best practice eg: at my previsou job I made the following improvements.

Good luck
Olivia
Speaking about Presenting