I am pretty much in a cardboard box with tin foil walls and mirrors on the ceiling and floor.
plenty of people use pretty much what you're using to grow in, so i'm not gonna bust your balls over it, i'll just say it's not the best of options and leave it at that..
you'd be fine with that setup, the only problem i have with it is the tin foil on the walls.. tin foil is a big no no for the most part, but you can simply spray paint the walls of it instead of the tin foil with some flat white paint imo..
oh yah, i'd ditch the mirrows as well.. if you got a bigger lamp like the ones we've been linking you with, than you'd have no need for a top anyhoo's as this is where the lamp would now live at, lol..
if you have to use the box as it's the only thing you really have, go for it.. but if you have say a small closet i'd say it would be the better option.. you'd be surprised and what a small closet grow could produce once dialed in..
another option that is very popular today are these grow tents that people use.. they come in all different sizes for say one plant all the way up to god, i don't know how big, but you could probably hold a circus under some of them, lol..
growing is pretty much like any other hobby that you can get into.. there are the basic setups for minimal money, than there are setups that are as elaborate and pricey as the person building it.. it's really up to the hobbyist to decide if they wanna dive in at the deep end on in the shallow end or some where in the middle.. i think some where in the middle is a nice spot, you don't have to spend tons of cash, yet can still get nice buds from it, and it won't be a let down and stop you from trying to grow again after a disappointing first grow due to crappier equipment..
...https://www.rollitup.org/newbie-central/499298-grow-videos.html