I've done research on building a custom home, somewhat upscale and I've received from 6,000 to 9,000 Pesos per m2. A good average would be around 8,000 Pesos m2. These do not include appliances, solar panels, pool or anything very fancy.
Another issue is cost of land. It's NOT cheap. Price will depend on view, which town, which development, etc. If you have a nice view, you'll pay between 2,000 to 3,500 Pesos m2.