In regard to the “I can’t do it anymore, I’m tired” comment he made…My children have been known to do this in the past. I simply respond with, “Well, what happens when I’m too tired to cook your meals or wash your clothes? I guess you’ll have to starve and wear stinky clothes!” It took a few times of saying that before they understood that jobs are important and have to be done, whether you want to or not. You may have to explain that more simply for your 3.5yo.
I totally agree with praising him like crazy for even the smallest of tasks completed. It will encourage him to do more because he will want more praise.
Also, rather than a list of chores, you could take a Polaroid of the jobs you want him to do. That might be a fun way to get him to enjoy chores. Some ideas for things he can do: unload and sort the silverware from the dishwasher, empty bathroom trashcans, straighten stuffed animals on his bed or decorative couch pillows in the living room, help fold laundry, help set the table (by putting out napkins or silverware), help clear the table, wipe baseboards, use a hand-held vacuum to clean up crumbs on the floor after meal or snack times. Our children each had their own hand-held broom and dustpan for sweeping up crumbs after meals. They thought it was really fun.
Hope that helps,
Lindsey