Hi mama! Try checking Facebook Marketplace at Carousell, maraming moms doon nag-sell ng preloved baby stuff, and you might find fetal dopplers na mas mura, especially sa Marikina area. Pwede mo ring try local parenting groups sa FB na Marikina-based, kasi a few of my mum friends nabili nila doon ng gently used items at nakakuha pa ng good deals!