Favorite mattress under 2k

Looking to finally get a new mattress for background me (160lb) and my partner (200lb) our two children also sleep with us ages 1 and 3 we've been sleeping on a hand me down sam's club beauty rest memory foam for the last 3 years, the mattress was already sagging when it was given to us for free but at the time we just were taking what we could get.. now we are looking to get a decent mattress. I struggle with low back and sciatic pain and my partner struggles with upper back and neck pain. He's a side sleeper I am mainly back and side. I want something firmer but he doesn't want to feel like he's laying on a plank would like to stay around 1300-1500 but if there's a great mattress for closer to 2k we're willing. What mattress do you have and really love