Consider changing your plans to take the DM course in Utila or Roatan; they're both common destinations for taking the DM course on a budget. When I did mine in Roatan, many of the DMTs on the island had very limited equipment, they could stay in a dorm owned by the dive op (coconut tree divers) for $5/night, and the course cost was $600 plus another $150 or so for materials.
Some of the DMTs moonlighted as waiters and/or bartenders in the evenings to raise a little cash. Occasionally they looked pretty green on those early morning dives!
I would not borrow money to do your dive training until you get to the IDC, which is more expensive. You won't make any money in the dive industry until you complete the instructor course. If you enjoy learning to dive, and make it through all the other courses (OW, AOW, rescue, and DM) plus complete the requisite number of dives (100, maybe?) to get to the IDC on your own dime, you've demonstrated good dedication and resourcefulness. At that time, one you've established your ability to stick with it, maybe it would be appropriate to go into a little debt to complete the IDC which will allow you to make back some of the money. (Not much, though)
Have fun!