Sister selling T-shirts in Cambodia

My sister has recently set up a small T-shirt shop in her boyfriend's bar in Cambodia. Now she wants her product range to include t-shirts she has printed herself, but she doesn't know which printing solution would suit her needs, and it's hard to trust the advice of local salesmen.

Her budget is limited (around €1000), and she will be printing small volumes of shirts to compliment her usual range. Nobody wants dark t-shirts in Cambodia, so she won't miss the ability to print on dark fabric. With this in mind, what kind of printing solution would you recommend? Advice on specific models of hardware is very welcome, but given that their availability in Cambodia may differ, we're mainly interested in knowing which type of technology to go with (dye sublim, dtg etc).

Also, she's been offered a printer with an included heat press that they claim will print to, and do transfers from, any normal paper. Is there really such technology, and if so, what is it called and is it suitable for my sister needs?