Keep in mind these RV jacks mentioned are not designed to lift and level your trailer but to stabilize it. Your least cost would be to use leveling blocks under the wheels then stabilize them.
12 volt electric on corners is expensive to do but can be done.
Unless you have unlimited budget bring 4 of either up from the U.S. will get you best bang for buck even with exchange & shipping. We get hosed up here on these items as I have gone this route myself. Do some homework and there are deals to be found on top of that and some will help with shipping if you bring it up. Buyer beware.
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