Keep a beady eye on FB marketplace or any other local sales sites - join a few groups. I've had some absolute bargains off there, our house is slowly beginning to resemble a nursery :o
Latest additions are IKEA play tunnel, and a slide bed with tent attachment. He won't sleep in it yet, he's still in a cotbed with the side on, but it will come in useful once the baby is bigger, and in the meantime it's a fantastic play addition! Ride on toys are also a big hit. I like the IKEA tunnel because you can fold it down for storage.
Friends have had success with ball pits - travel cot, inflatable paddling pool or pop up tent thing can contain the balls. And mini trampolines!
At about age 1 there are some god awful "activity tables" which they absolutely love but are a bit of a monstrosity. FB marketplace is great for those because you can sell them on again once they're past that age.