After a job Julie sends her invoice for $2300 to the client, Tina. It states that it is payable within three business days. But two weeks later, Tina still hasn't paid. Julie calls her to follow up. "Yes, I know, you'll have it soon" says Tina. But another two weeks go by and still she hasn't paid. Julie decides to show up at Tina's business to demand payment. Tina says she doesn't have the cash to pay the whole account right now. "That's hardly my problem! What do I have to do to get you to pay?" says Julie. Tina responds: "Well, you could try taking me to court... but it wouldn't change the fact I can't pay you right now. How about this instead?" Tina then suggests that she pays Julie what she can right now, which is $1500, and then also provide her with a personal reference to Tina's aunt Tania who works in state government. "Tania manages projects every month which need traffic management. You'll have more jobs than you know what to do with! Tania trusts me; she'll be happy to use your service." Julie reluctantly agrees.

using IRAC problem solving method(Is the new agreement between Tina and Julie legally binding? according to Australian law which case law applies?