There are a lot of hardware stores in Puerto and some are better for some people and some are better for other people. Some are better for some things and some are better for other things. Having said that I usually go to Materiales del Puerto because it is very convenient. The people there treat me very well. They have most everything I have needed too. The reason they are so convenient is because they are right down the street from Ahorrara and on the way to the highway from the Mercado. Like a lot of hardware stores they deliver as well.
Another hardware store that I like is Ferretodo up by the Post Office across the street from Acario stationary store. It is a good hardware store because everything they have is hanging or right there in front of you. This comes in handy if you don't know how to say something in Spanish. The people there are nice too. Prices are in the ballpark and they don't seem to give the gringo discount. This is true with Materiales del Puerto also. There are hardware stores that the contractors or people who are building houses like because it is easy to get credit and they may be able to offer better discounts for larger orders. Of course I am talking about Zimat. The people there are nice enough and everything but I seem to like the other two places that I mentioned better.
Just don't get me started on the House of Screws. It's the best screw store in Puerto by far. And in their new location they are a bit hard to find. They do have every screw in the book and bolts to beat the band. Well it just doesn't not get any better than the house of Screws. Big bolts, little bolts, long bolts and short bolts. They have washers that will make your head spin. The thing that they have that is/was hard to find was the ever handy sheetrock screws of every size. The only problem is, you have to buy them by the piece as opposed to by the pound. It takes a while for them to count out a hundred and twenty three 1-inch screws. But it is worth the wait because while you are standing there you can check out the walls and see whatever else you may have forgotten. They have some cool tools there too but you don't really want to go there to buy tools unless it is something off the wall that you can't seem to find anyplace else (how's that for a pun). So if it screws you need, "House of Screws" is the place to go. It is located in the same neighborhood as Ahorrara and Materiales del Puerto and Armando's office. If you go down toward the highway from Ahorrara and get to the first stoplight right near the street where the Pemex station is you take a left and go one block and take another left and it is on the left hand side. I think it is Second Street. You have to guess if it is Second Street North, South, East or West (I think it is Second Street East).
If you are down at the Point and you need a pipe fitting or some chin link fencing or even a shovel and don't want to hassle the rush hour traffic you should go to Materiales Brisas (or something like that) that is on the highway right where the street from the Point comes out. They have more and more stuff every day. I remember when they didn't have much more than a few different PVC fittings and now they seem to have almost everything (key word - almost).
That is about as much as I can help you with hardware stores in Puerto Escondido.