I’m still stuck on the fact that you’re Realtor has shown you 100 homes! Hell, he’s spent a boatload of his own dough just driving you around. I don’t think he would try and screw you over after all that but he should submit any offers you want to write.
The bottom line is, work out the numbers and submit the offer you are comfortable with. It may be low and it might not get accepted but stick to your gut feeling and don’t let your emotions talk you into a bad decision. If your Realtor has a problem than get another one… they’re everywhere!