Honestly, getting a Sony Alpha 7 IV 33MP Mirrorless Body for under 2k brand new is basically impossible right now. I remember when I first started, I tried to save money on a cheap deal from a random site and it was a grey market camera with no warranty... total nightmare. Since youre worried about scams, I would suggest checking out MPB or KEH instead of eBay. I bought a used Sony Alpha 7 IV 33MP Mirrorless Body from MPB last year and it was much cheaper than retail. They actually inspect the gear and give you a short warranty, which is way safer for a beginner. Make sure to check the condition ratings carefully tho. $1900 is still a bit tight for an A7 IV even used, but sometimes you can find well-used ones that work perfectly. Just be careful with those too good to be true prices.

In my experience, you're not gonna find a new A7 IV for $1900 unless it's a total scam. Over the years I've learned that buying used from reputable shops like KEH or MPB is way safer than rolling the dice on eBay. They actually grade the sensors and give you a return window so you dont get stuck with a brick. If you're firm on that budget, honestly look at the Sony Alpha 7 III 24.2MP Full-Frame Mirrorless. It's still a pro-level workhorse and easily fits your $1800 limit with room for a lens. Or check out the Sony Alpha 7C 24.2MP Compact Mirrorless Camera if you want the same tech in a smaller body. Florida weddings are brutal with the heat, so a lighter rig isn't a bad idea anyway. Don't forget you still need to buy glass tho... a body without a lens is just a paperweight.

Late to the party but I wanted to add my two cents because I went through this exact stress last year. If your absolute hard limit is $1900, you might want to consider whether the A7 IV is actually the right move for a wedding in Florida. That heat and humidity are no joke for electronics, and more importantly, you still need to buy a lens. If you spend your whole budget on just the camera body, you are basically gonna be holding a very expensive paperweight during the ceremony. I would suggest looking into the Sony Alpha a7C II 33MP Full-Frame or even the older Sony Alpha a7 III 24.2MP Full-Frame. The a7 III is still a total workhorse for weddings and you can easily find it for around $1300 used, which leaves you money for a solid lens like the Tamron 28-75mm f/2.8 Di III VXD G2 for Sony E. You really need that f/2.8 aperture for indoor shots or those evening receptions. One resource you should definitely check is the B and H Photo EDU discount program if you or a family member has a student email. The savings can be huge. Also, make sure to avoid those random shops that show up in Google Shopping for $1500... those are usually bait and switch scams where they call you after the order to say the battery or charger isnt included. Stick to the Open Box section at Best Buy or the official Sony refurbished store to stay safe.