Large new or used flat screen tv (Las Vegas, NV)

Hi I've never had a new tv or anything larger than a 40 inch tv ever in my whole entire life because of my financial instability. I saw a 70 inch Roku smart tv at Walmart yesterday on rollback for $448. I'm wondering if someone could get that for me or bless me with a used or new flat screen tv larger than 40 inches. I'm a permanently disabled military veteran who is unable to work or have any regular steady source of income in order to buy anything after becoming permanently disabled while serving our country honorably on active duty in the US Army. I do receive a monthly VA 10% service connected disability check for $152 a month that basically covers my car insurance & gas & nothing else which leaves me little to nothing left after that.