get a tent and then take the reflective tape they sell for tents and tape off all the zipper parts, then get in it and look for more leaks and then patch with tape. If it's in a closet or a unoccupied room then it doesn't really matter just keep the room it's in dark. There's some really cheap ones out there so def look around. Cheaper made don't last forever, have shittier zippers etc. just take the money buy some wood, panda film etc and make something