Also if you want to save some money you don't must buy a Mac. There is other ways how to do it:
1.) You can use practically any OS to run latest MacOS in virtual machine (look at YouTube). I am using this method really long time without any problems on windows with VMWare.
2.) Hackintosh. Install MacOS to your PC. You must have compatible components, but if you have, this is the best way, because you eliminate the lags in VM... I am using this in this time. Perfect. On my laptop, but please don't tell this to Apple, because practically this is illegal
3.) If you are making simple apps with minimum UI, you can use Theos. Also with Theos you can create cydia tweaks. Only one problem: codesign. If you want to publish app on App Store you still must have MacOS, but if you want to make app in home you can use CydiaImpactor to sign the apps with Apple ID.
I used all of this ways and all is working. By my VM is best solution if you don't want to spend lot of time by installing Hackintosh.