2) I also note that it does not take long before doors start to sag & the gaps become irregular. Not hard to fix just lie on your back, take all doors off, then tighten everything & replace – then take a cold shower you will need it! It seems the cup sections remain well fixed but the fixing plates on the inside of the cupboard sides just work loose. This ought not to happen but it does & with all the concealed overlay hinges I have seen. Is there an answer? I suspect the hinges are under rated, 2 hinges for doors that typically are nearly 10Lbs may be the reason. Can you please comment.
There are also a couple of overlay sizes, most commonly  1 1/4″ and 1/2″. Overlay refers to the distance your door overlaps your opening. Mine didn’t measure 1 1/4″ or 1/2″, and this project still worked with my doors. If you’re looking for information on how to measure your overlay, this is not the post for you because I haven’t the faintest idea. Back to Google you go! (Sorry!)
Knobs, which are attached with a single screw, are most frequently used on cabinets, and are available with a built-in screw, known as a one-piece knob, or with a separate top and fastener, known as a two-piece design. Modern drawer knobs are made in a variety of materials including brass, zinc, stainless steel (sometimes found in kitchens), bronze, glass, crystal, plastic, wood, and other natural and man-made materials. 
It’s important to choose hardware that will complement the rest of your kitchen décor and accentuate its worthy features. Generally, most people want their cabinet and drawer hardware to coordinate with the handles on their appliances. The colors should work well together, and the finishes shouldn’t clash. Drastically different shapes can also make your kitchen feel cluttered. You should use functionality and your personal preference to approach choosing knobs vs. pulls, but there are a few general guidelines to follow that correlate with your style of cabinets.
Generally speaking, I like to see a combination of knobs and handles/pulls. Knobs or handles for the doors and handles or pulls for the drawers. If you are painting your kitchen, the extra holes can be filled, sanded, and smoothed prior to painting so you can start with a clean slate and choose any hardware for your update. I say “generally speaking” because lately I’m drawn to kitchens that have all handles like this “before” photo of a kitchen we recently updated.
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