Thanks for writing in Frida; and welcome to our community! I think you’re already ahead of the game by asking this question. I think I can speak for many people here when I share that I started out by spending way too much money on gear before I knew what I was doing--or at least, more money than I needed to spend. If I’m being honest, I overspent because I thought having better gear would make me a better photographer. I quickly found out that working hard to get better made me a better photographer! That said, you’ve also made an important distinction by asking about the “best way” to spend money, rather than “how much”. This says that you’re more focused on priorities rather than dollars out, which is a good thing.
First, I think you already have a decent camera. The Nikon D5600 model has been around for about 10 years but it will be more than enough to get your feet wet in real estate photography. In terms of priorities, there are a couple of things that I think ought to be at the top of the list: your lens and your tripod. A good lens will always be your most important piece of gear and, all things being equal, will always last longer than a camera body. A good lens will also have better optics than cheaper kit lenses. I don’t know what lens you had on your camera to do your first shoot but moving forward, you will need an ultra-wide angle lens. For a list of the possibilities, see the PFRE lens table that shows many of the major choices and the results of several reader polls on the most popular lenses in our field. The list is a couple of years old, but I’m confident that you’ll be pointed in the right direction.
The other major piece of gear that you’ll need is a good, stable tripod to make sure your camera is as still as possible when taking shots. Check Craigslist.org, eBay.com, or Amazon.com for used equipment. The odds are that you can save quite a bit of money by purchasing used gear.
Also Frida, I’d guess that a vast majority of folks in our field use flash in their work. You don’t need to spend a bunch of money on a new flash. Many people here start out by using a “third-party” flash and trigger from a company called Yong Nuo. You can get a manual flash from them for about $60.00USD and I think you should have at least one of those.
So, what other items do you think should Frida should/shouldn't skimp on as she gets started?