There are a few cheaper guns out there but they are few and far between.
I started with an AFTERMATH MP5 Broxa, built like a tank, very few failures and got it for under $200. After several years of play, put a new hopup and tighter barrel into it. Still love it. But I've seen others that got them and they died within a few games.
Better to get age verified here and pick up something from somebody bailing from airsoft. You can usually get a good gun at very reasonable prices.
Plus after I got the Broxa I spent another $800 on mags, batteries, case, boots, eyepro, BDU, bbs, chest rig....etc. This is not a cheap sport.
Nothing says loving, like a head shot!