No you haven't quite got it - if the OP uses a board in the conventional way he will need 4 layers and probably 5 thou track and gap design rules. He'll pay well over $50 for one and will need to wait a couple of weeks (or well over $200 and have it in a couple of days.). But even when he gets the board he will have trouble soldering it. If he wants just one, tomorrow, and has no cash the home brew pcb with hand crafted copper slug makes perfect sense.
I don't etch my own boards any more because it's more cost effective for a paying customer to use a pcb house rather than my time. My kids have different budgets/priorities and have etched their own - it's actually quite a lot of fun.
Michael Kellett