I've never heard of anyone I know ever having to "rebuild" a pump for their pressure washer.. Number one rule, - DO NOT let the machine run without spraying water for more than a minute or two.. Anything more, shut it off, restart when you are ready..
Just some things I've picked up from using mine for so long. - don't waste money on some fancy expensive wand with a bunch a plastic and **** around it to make it look cool.. It's a waste of money, and anything unnecessary just adds weight, which ***** if you have to hold the wand upward for a long time. Buy a cheap, basic, bare boned wand. Take the handle apart and remove the trigger lock. Buy a basic medium length metal tub extension, that you can use with a clamp on type secondary handle, that you can clamp anywhere, at any angle, around the metal extension tube.. This is the lightest, toughest , 2 handle wand set up. Buy a 16" surface cleaning attachment from HD / lowes / Amazon..(about $60 or $70). I have the HD Briggs and Straton one.. It's ******* great - like the first time you ever used a nail gun great.. If you have a big area to work on, invest in a longer pressure hose.. You can get a 50' hose with the fittings off amazon for like $60 or so.. Most machines come with a 25' or 35'.. The 50' makes a big difference.. A water broom attachment is another great accessory. You can use the surface cleaner to lift all the dirt off sidewalks/driveways/patios, ad then switch to the broom to flush or "sweep" it away or into the street. Buy quick connect fittings for the garden hose.. It's SO much easier to put on, take off, and there's no struggling trying to unscrews hose ends that need to be tight to avoid leaking..
If you can find a machine you like for around $300 to $350, you can buy these cheap accessories to make the most of it, which will make your life much easier.. By all means buy a better machine for the $500 if you want to though, but the attachments make a HUGE difference in time and effort that will be spent using it. I would aim for something between 2800 - 3200 psi if possible, 2500 at a minimum, and maybe a machine that has an on-board soap/detergent container.. If you have to compromise - there is a clamp on gallon bottle holder that can be attached to the machine's frame to hold detergent bottles that must be fed via a siphon tube..
Good luck - post whatever you go with..
PS - I went though 2 Husky electric 1800psi units before getting a gas, my father went though 2 electrics himself before buying ANOTHER one off amazon..
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