JSFiddle - React, Tailwind, and code Playground
JavaScript
var t =[ { "room": { "price": 217, "available": true } }, { "room": { "price": 302, "available": true, } }, { "room": { "price": 427, "available": true, } } ]
var min = t.map(function(el){return el.room.price}).reduce(function(el){return Math.min(el)});
console.log(min);