Please help me with this question: Paul wonders if the extra money is worth pursuing more higher revenue jobs?

Data:

Paul has some experience with building furniture, so he has started making tables and chairs himself. After customers saw his work, they also requested custom pieces, which he started charging a premium for. In the first year, House Tech completed 30 interior design engagements. Two-thirds of these were engagements where all major pieces were purchased. On average, the revenues totaled $6,000 for these jobs. The remaining third heavily involved Pauls specialty items, resulting in higher revenue of $9,000.

Paul estimates he spends $200 of material and 4.5 hours on an average per piece. He believes he made 25 pieces last year. By advertising $2,500 a month, the annual numbers could be increased to 40 engagements, half of them including significant specialty items made by him.

Thank you in advance.