I\'m using Visual Studio 2017 on Windows 10 with no Mac at all. When I try to debug a new Xamarin cross platform project, VS tries to locate a Mac.
Is a Mac pretty much
Xamarin requires access to a networked Mac to build and debug iOS applications. There is no way to perform a build for a native iOS app without a physical Mac, as Apple only makes the iOS SDK available for macOS.
From the Xamarin.iOS developer docs:
"iOS applications cannot be created without Apple’s compiler,
and they cannot be deployed without Apple’s certificates and
code-signing tools. This means that a Xamarin.iOS for Visual Studio
installation requires a connection to a networked Mac OS X computer
in order to perform these tasks."
https://developer.xamarin.com/guides/ios/getting_started/installation/windows/#Requirements
Your best bet would probably be a Mac Mini. You can find them used online to save a little money, or if you'd prefer not to buy used they sometimes show up on Apple's refurbished site: https://www.apple.com/shop/browse/home/specialdeals/mac
Another option might be to use a cloud option, but I'm not sure how the latency would affect Visual Studio when trying to build and it would likely make debugging difficult. I've never used one of these services, but here are two that I've heard of in the past: http://www.macincloud.com/ and http://www.xcodeclub.com/
Please also note that it is both unsupported and in violation of Apple's license agreements to attempt running a macOS VM on non-Apple hardware, even though it is technically possible.