They're both pretty damn easy, with a good partner. The chainsaw guy is easy no matter what, but to kill the axe guy before Kirk arrives with a lousy partner... it ain't happinin. The easiest way to kill the axe guy is cover Sheva on top of the bus or even inside the bus while she snipes him IN THE HEAD. Don't run out and punch him when he kneels down with a headache either, just have Sheva keep sniping him. He'll go down.(Smiles)
The other easy but so-so way is to lure him near all the gas tanks and canisters and blow him up or set him on fire. This takes practice though. There's also, by default, three hand grenades and an incindery grenade on the level so you can use those too. Also helps with crowd control.
As for Mr. Chainsaw, with a little preperation this fight is a breeze. First, clean house. Find every scrap of ammo in the area, DO NOT blow up any of the oil tanks and don't shoot the power box on the phone line above the stairs ...yet. Run over to the wooden door in the alley and knife it down so you can walk through freely. Head over to the stairway alley now. Have Chris stand by the last pillar to the left and aim at the power box whilst Sheva lures out the Chainsaw dude. Shoot the power box, it'll fall on his head. Clear out a couple of zombies, run to the end of the little alley to the left. Wait for the Chainsaw guy to be RIGHT next to the oil tank (the closer the better, can't always be picky though) both of you kick and/or punch him then run through the back entrance of the house, turn right, nail him with some rifle round in the head. Kick and/or punch him. (All the while trying to blow him up with the oil tanks) run to little alley, snipe. Repeat. Obviously there'll be more "shoot the oil can"s than I lead on, but go with what you can handle.
Hopefully this was helpful. (Smiles)