I am not a high carb, nor am I a low caber (by paleo standards). How many carbs you can eat without gaining fat will be determined by the type of carb (starch/glucose vs fruit/fructose), your level of insulin sensitivity, when you choose to eat your carbs, and the amount of glycogen depleting activities you engage in (also, probably, the amount of muscle you carry).
Personally, I love self experimentation, and have tried many different macronutrient strategies, ranging frm sub 20g of carbs per day all the way up to 450g carbs per day. In honesty, I felt physically the best at the high end, but it made keeping lean require tedious timing and meal structuring. Now I fall in the middle range, usually ranging from 100-200g per day. All i can do is relay my experiences to you. Simple carbs (honey, sugar, fruit) do much better for my composition when eaten in the absence of any fat. Best time for me is first thing in the morning or immediately post workout. Starches, I like a little extra fat. I get my fat mostly form animals, fish, eggs, and olive oil. My favorite starches are potatoes and Japanese sweet potatoes (only) and my favorite simple carbs are honey and blueberries. The more carbs you eat, the more you have to minimize fat if you're an athlete looking to recover from workouts.
ultimately you're going to have to experiment and see what works for you. Above is what works for me.
