A good laser engraver turns a hobby into a small business. You want a unit that can cut through wood and acrylic, not just etch them. These machines should last you years if you maintain the rails and lenses, so it is better to buy a mid-range workhorse once than a toy you will outgrow in three months.
Summer is when the big maker brands clear out stock for fall releases. You can usually find last year's flagship models at a steep discount during July flash sales. If you use the Discover it® Cash Back, you can spread that cost out over 15 months.
Remember that the 0% intro APR for 15 months on purchases and balance transfers is a hard deadline. If you still have a balance when those 15 months are up, you will get hit with the standard variable APR on whatever is left. It is a tool for cash flow, not a way to avoid the bill forever.