It's quite demoralizing for a lower levels that we do not have any way to prevent, hide in general. 

I think there should be a way a unique way, to prevent attacks. I think any of the below should do just great!

1 Allow attacking another person only if they are engaged in an active outdoor activity.

2 a totally different way to resolve this I think is to make a big city map of a lot of different places you can choose to hide.  A person who wants to hide cannot participate in any job activities. The only exception I feel would be if they have narcos following them then the narcos can do their bidding while they are hiding.  A person can click hide and then choose a random spot on the map, this random spot could hide the person for a random number of hours but no more than say 3 hours.  If a person wants to attack another person who is actively hiding they have three chances to guess on the map where they are hiding and if they guess correctly then maybe a little bit of their intelligence goes up, and they get to attack the person. 

I feel that active people would be able to benefit from this and inactives would be obviously punished for it. And rightfully so. I hate for us to copy other games and self-hosp.

In conclusion I would say self-hosping but I think that's a cop out for obvious reasons.  I'm just thinking out loud as right now there is no way to prevent someone from farming you especially since there are apparently not that many targets I guess.

I think some sort of self-hosping mechanic that maybe provides some sort of stat debuff may be a good idea. It allows you to avoid attacks for some time but does also provide some disadvantage for doing so.