Newbury after advice from you guru's!

Hi people!

I have an idea for a website that I want to develop. Im a newby and so My plan is to take my time enrolling on online courses and utilising the many books out there to start learning, however I'm not expecting to be anywhere near capable to complete the majority of my requirements anytime soon.

What I would need is a site that requires users to securely log in, then once logged in they can if need be upload spreadsheet data to a database e.g workforce personnel detail and qualifications, hours worked etc.

The site would be used to cover staff shortfalls at certain venues, so all venues would be on the system.

I would also want the site to calculate distance travelled from one point to another to calculate cost, then select the most cost effective option out of these e.g if it's 50p per mile to travel It would choose the closest option.

The system would be configurable by each user to suit their requirements eg how many hours before overtime kicks in etc
The system would then calculate the cheapest option.

How would I go about this? Would I be better paying a developer to do most it not all of this?

Thanks in advance!