Ken in Georgia says:
These days, I'm getting more and more requests for video. I have a Nikon 5300 with a Sigma 10-20mm but I am not getting the video quality my clients expect. I have been looking at the Sony A6300 or A6500 but I don't want to drop and a grand or so if I don't have to. I have a Zhiyun Crane 2 that does struggle a bit with the 5300 weight. I have researched. Made decision matrices and basically gotten myself flustered. Should I take the Sony A6300 or another hardware route entirely?
As you've found, the Nikon D5300 will do video but it is 5-year-old technology and Nikon has never been known for its outstanding video. However, the Sony A6300 and A6500 shoot 6K video which is down-sampled to 4K. I think you and your clients would be much happier with if you moved up to at least the A6300.
The primary difference between the A6300 and A6500 is that the A6500 has 5 axis stabilization and will shoot faster still frames (for details see this video). Some would argue that for shooting interiors the A6500 is not essential. But the difference in cost is only $200.
As for a lens, I would recommend a Sony 10-18mm f/4.
If you already have this camera, you might be interested in our review of the best flash for the Sony A6300.