Costs are determined by what is required, how you would like it structured and whether we are running any special promotions at the time.  The best approach is to talk to us about your requirements and we will discuss cost as part of the conversation. 

I am a graduate and do not have any spare money.

As indicated above the best thing to do is to talk to us.  We have worked successfully with many graduates in the past.  One option is to get together a small group of friends and split the costs.

What guarantee's do I have about it being successful?

There are no guarantee's about anything in life.  If you are not satisfied at any point then after exploring all potential options then it would be best for both sides to move on.