Hi Big Al,
I'm no expert here, but I do use Eco-Flow products and for my use they are great, BUT in the motorhome I've been a bit disappointed TBH.
That said All Power/Eco-Flow/Blueetti/Jackman etc all have prices bouncing up and down much of the time. The Eco-flow Delta 2 Max is ON OFFER at £1599 just now, which is odd because I bought mine for £1199 and the Extra
battery is now available at £999 but I paid £749
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had a second Extra
battery delivered today said reconditioned but its actually brand new cost £799 but then I had some ecoflow vouchers so actually paid £651
I also have eco-flow
solar panels, but again got a deal with the Delta2 max.
They also offer members only pricing as do All Power and Blueetti so before you buy sign up as a memeber for all of these companies and keep an eye on your in box, but decide what you want first and don't be fooled by marketing ploys designed to make you spend more be patient a deal will come along.