Calculate the total production cost for Job XXX1, including materials, labour, and overheads, and then the total cost of sales.

$$\text{Total Material Cost} = \text{Opening Material} + \text{Current Month Material}$$ $$\text{Total Material Cost} = \text{R}25\,000 + \text{R}105\,000 = \text{R}130\,000$$

$$\text{Total Labour Cost} = \text{Opening Labour} + \text{Current Month Labour}$$ $$\text{Total Labour Cost} = \text{R}18\,000 + \text{R}85\,000 = \text{R}103\,000$$

The current month's applied overheads are R15.00 per unit for 6 000 units.

$$\text{Current Month Overheads} = 6\,000 \text{ units} \times \text{R}15.00/\text{unit} = \text{R}90\,000$$ $$\text{Total Applied Overheads} = \text{Opening Applied Overheads} + \text{Current Month Overheads}$$ $$\text{Total Applied Overheads} = \text{R}62\,500 + \text{R}90\,000 = \text{R}152\,500$$

$$\text{Total Production Cost} = \text{Total Material Cost} + \text{Total Labour Cost} + \text{Total Applied Overheads}$$ $$\text{Total Production Cost} = \text{R}130\,000 + \text{R}103\,000 + \text{R}152\,500 = \text{R}385\,500$$

The selling and marketing cost for Job XXX1 is R0.

$$\text{Total Cost of Sales} = \text{Total Production Cost} + \text{Selling and Marketing Cost}$$ $$\text{Total Cost of Sales} = \text{R}385\,500 + \text{R}0 = \text{R}385\,500$$

Job XXX1 produced 6 000 units and was invoiced at R65.00 per unit.

$$\text{Sales Revenue} = \text{Units Produced} \times \text{Selling Price Per Unit}$$ $$\text{Sales Revenue} = 6\,000 \text{ units} \times \text{R}65.00/\text{unit} = \text{R}390\,000$$

$$\text{Profit} = \text{Sales Revenue} - \text{Total Cost of Sales}$$ $$\text{Profit} = \text{R}390\,000 - \text{R}385\,500 = \text{R}4\,500$$

The completed job card for Job XXX1 is:

$$\begin{array}{|l|r|} \hline \textbf{Job Card: Job XXX1} & \textbf{Amount (R)} \\ \hline \text{Direct Material:} & \\ \quad \text{Opening Balance} & 25\,000 \\ \quad \text{Current Month} & 105\,000 \\ \quad \textbf{Total Direct Material} & \mathbf{130\,000} \\ \text{Direct Labour:} & \\ \quad \text{Opening Balance} & 18\,000 \\ \quad \text{Current Month} & 85\,000 \\ \quad \textbf{Total Direct Labour} & \mathbf{103\,000} \\ \text{Applied Overheads:} & \\ \quad \text{Opening Balance} & 62\,500 \\ \quad \text{Current Month (6 000 units} \times \text{R}15.00) & 90\,000 \\ \quad \textbf{Total Applied Overheads} & \mathbf{152\,500} \\ \textbf{Total Production Cost} & \mathbf{385\,500} \\ \text{Selling and Marketing Cost} & 0 \\ \textbf{Total Cost of Sales} & \mathbf{385\,500} \\ \text{Sales Revenue (6 000 units} \times \text{R}65.00) & 390\,000 \\ \textbf{Profit} & \mathbf{4\,500} \\ \hline \end{array}$$

The profit for Job XXX1 is $\boxed{\text{R}4\,500}$.