Chicken coop for my chickens

Hello there! I am trying to buy or build a chicken coop for my chickens, they have a cage now and are well cared, but I would love them to have more space and to be more comfortable. I've seen chicken coops at Costco and the cost about $12,000 (pesos), which would be around $600 (dollars). With the money I would buy the a coop or either build them one and get them some nice feeders. I have three chickens and they roam freely now, but there are cats out there and I am worried about them. Also, I would like them to get their coop before winter arrives.