We all have to balance considerations of time versus money versus keeping-your-significant-other-reasonably-happy when dealing with our hobby. Nowhere is this truer than when it comes to terrain.
You can see some truly astonishing home-made stuff on the internet, but much of that takes a long time (and a certain amount of talent) to make. Conversely, you could buy everything you need as pre-painted resin sculpts, but probably not without selling your car to raise enough money.
Like most other adults with families and full-time jobs I know, I’ve certainly got more money than time, but even so I cannot afford to buy everything I’d like to. For a long time that meant not buying any terrain, as I don’t actually play very many games. I did print out some paper buildings and even assembled a few of them, but that was it.