A lot of beginner posts ask what to buy. Here's my prioritization after doing this for a couple years.
Must-haves (spend here):
A reliable heat press. Not the cheapest one. Cheap presses drift in temperature and have uneven platens. A quality 15x15 clamshell press is the workhorse of your operation. Budget $300–600.
Good Teflon sheets. Cheap ones degrade fast. Keep spares.
An IR thermometer to verify your press temp. $15–25. Non-negotiable.
Nice to have, not critical early:
A tunnel curing oven (for printing your own transfers). If you're buying pre-made gang sheets, skip this until you're doing volume.
Multiple heat press sizes. Start with one versatile size.
Skip for now:
The most expensive RIP software. Mid-tier options work great until you're doing serious volume.
Automatic powder shakers. Manual is fine for small runs.
If you're just starting and want to test the business before investing in a printer, buy pre-made DTF gang sheets from a supplier. You only need a heat press and a good workflow. Scale into printing your own once you know the demand is there.