@Coult45 , I can’t find the post with the parts list now but here is what comes to mind:
1. Wash down pump kit from west marine. Usually 3 to 4 gpm, kit comes with pump, hose attachments, filter and spray head for around $200. They offer higher capacity / output stand alone pumps as well.
2. small 12v battery, I use arm because they are sealed (no vents). Another $100 or so.
3. Small or large battery box, $15.
4. a 1 to 5 pound weight to hold the intake hose and filter down, under $5.
5. Hoses, between $10 and $20.
Not inexpensive but great for its uses so far
I have heard you can go cheaper by buying a pump from harbor freight but their pumps cannot be run dry, at least not for long before they die.
This is a basic unit I put together from old parts (I still need to secure the pump to the battery box wall so I can remove the foam separating the components to create more space for the hoses, weight, filter and head when the gun is not in use. Once upon a time I installed this (larger pump actually) in a rolling cooler with an amp and speakers for lazy river rafting water fun fights.
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