I buy used gear. I got my red sea 130dd with stand pumps, rock etc for $250. I got my wife a plug and play 32g led biocube for $140. I'm already buying up used equipment for a vague future build. Equipment can be had for a song if you're patient. I got a Kessel h80, Milwaukee digital refracto, a UV, 2 media reactors, NIB jebao auto doser, 2 slw-20, jebao gyre, submersible return pump, 8 maxijet 1200, and a half bucket each of reef crystals and phosguard for $150. Keep an eye out for people breaking down tanks. The 2 lfs I go to have a huge selection of nice fans from $5-50, and 1 does a weekly online auction.
I also diy stuff. My dosing station is made from a cardboard box and containers from the dollar store. I've tried hard to buy gear that I can use on a bigger tank too when I'm ready to upgrade.