Yesterday GPT asked me if I'd like to train a small LLM and I laughed out loud.
That being said I'm amazed how far 1B models have come. I remember when TinyLlama came out a few years ago, it was not great. ($40K training cost iirc.)
That was a 1B model, but these days even 0.5B models are remarkably coherent.
And the GPUs would be a shared resource so what you should calculate is what it would have cost to rent them - probably something like 2 m.