For starters - it won't be cheap, if you want decent quality PTZ cameras. Also NVR/DVR will be better choice than PC as a recorder(software ain't cheap). Or you can buy something on aliexpress and pray that this'll work when you need it.
IMHO - I've recently seen something like Dahua TiOC camera and I'll go for it, then NVR(with built-in PoE switch, or external PoE switch - if you want to power it that way) with WizSense - and you'll have decent quality without spending ton of money. And forget about PTZ, around house it's pointless. Cheaper option is to use analog hardware, it isn't as bad as a lot of people says. Except situations where 8Mpix isn't enough... Your choice. I've built CCTV for small place(like around a house) with Dahua analog CCTV - 3 8Mpix(HAC-HFW2802E-A-0280B, it's discontinued but has good 1/1.8" CMOS sensor) cameras outside, 3 5Mpix(HAC-HDW1500TLMQ-A-0280B-S2) cameras inside, WizSense XVR(HDCVI 6.0 Plus - XVR7208A-4K-I2). Price is reasonable, SMD+ will do its work when needed, and maybe even alarm out... And I'll suggest something like this. Good thing is that you can go up to 4K using UTP cable - passive video converter like PFM800-4K plus DC connector and you can have one UTP cable to power a camera and send image through it.