Your best bet is an NVR and IP cameras, the vast majority of kits on the market are POE and the quality is actually very good for the price, Dhaua & Hikvision are the most prominent in the budget market, the high end systems are thousands of dollars just for the hardware.
You do NOT want wireless cameras if you’re trying to cover 5000 sqft, they will end up costing more in the long run because WiFi is limited to the distance it can send HD quality video.
Also about 1080p & 4K cameras, yes they look fantastic but they use a lot of bandwidth and storage space, I have 3 4K cameras and a 1.3mp camera on my home NVR system and I have to turn the quality way down to stream the video, with 3 cameras at 4K and 1 at 1.3mp it eats all 20 Mbps of my internets upload bandwidth, IE my internet chokes and I look at still images when I try to stream, plus with all 4 cameras set to record based on motion activation I get about 8 days of recorded video.
I set all of my camers to 1.3mp and 20 fps recording quality and I get about a month of recorded video and the quality is still damn good but it doesn’t hammer the living crap out of the HDD, to view the video remotely I turn the streaming quality down to the point that each camera uses about 1 Mbps which is still very viewable on a tablet or a cell phone.
With all that said an 8 channel NVR and 8 cameras will run you about $1500 to $2000 (or more) to install, if you have good enough internet then by all means go with 1080p to 4K cameras, but if it were me I wouldn’t go higher than 2mp because 8 cameras at 2mp will uses ton of storage and bandwidth as it is and I could honestly show 100 people a 4K video clip compared to a 1.3 mp camera and maybe 5 of them will be able to tell the difference, imo it’s the sweet spot when balancing quality and Usability.
I have been doing security systems, access control, fire alarms, cctv and IT for 27-28 years but I don’t claim to know everything, but as a service tech I’m the guy that has to go out and explain to customers why their very expensive NVR & 4K cameras won’t stream properly because either they don’t have enough upload bandwidth or they are trying to download 20 Mbps worth of video on a 10 Mbps internet connection, well it looks like crap because in order for you to view the video I have to turn all the wizzbang ultra HD settings down to 420p so it’ll work......
Anyways I hope any of this rambling helps, feel free to let me know if I can answer any specific questions.