Hosting location

Does the location of hosting affects google ranking? Like if I want to target US visitors and my host is in Europe would that be bad (with the exception of latency ofcourse) ?

Generally speaking, it's a good idea to get hosting in the same country or continent that you're targeting for traffic. I've had hosting in both the UK and India, and my pages never ranked for their keywords in the US, but I have several pages ranking for very similar keywords to the ones that I used with the "foreign" hosting, and they're hosted in the US and ranking well in the US version of Google.

It changes but sure has effect. Moreover, no one can tell you the exact effect.

Better to host in the us.

It is likely cheaper and will be better ranking for for searches from the US.