Company I applied to is going to make an offer me tomorrow. I feel like they will try to kinda lowball me. Is it rude to ask for lets say plus 10 percent as soon as I receive the offer ? In your experience have you did this and how it ended?

Didn't they ask about your expectations before making you an offer? Usually if you gave a reasonable answer, they will either match it or try 5-10% lower. So I guess if that's their strategy, you could do the same in the opposite direction. Handle it diplomatically.. I notice you get more leverage with experience, when you're already employed, and if you have multiple offers lined up though