I did look at some Lithium that were "cheap" but discounted them because with tech moving so quickly, they are liable to be older generations of these batteries. I may be wrong though. We have Bluetooth on our solar controller, so not worried about the battery having it. One thing I did think of, these three weight a staggering 70kg! Three Lithium would be much lighter, although only 100AH. So if weight was an issue, I would have probably gone to look deeper into the cost of them and the necessary upgrade.£140 buys a lith 100 ah unit, but im the same as you and only do a overnight when away, i bought 2 90ah lead acids now over 10 years ago and still do lights and run a 230v small fridge for 24 hrs no bother, when they die i shall go lead carbons saving expensive units to change.
Thing with Lead Batteries is weight tells you a lot. I wouldn't actually call 70Kg staggering for 3 x 100Ah decent lead acid Batteries. (The 3 lead carbon batteries I fitted in my previous van were 210Ah a piece and they were 71Kg EACH!)I did look at some Lithium that were "cheap" but discounted them because with tech moving so quickly, they are liable to be older generations of these batteries. I may be wrong though. We have Bluetooth on our solar controller, so not worried about the battery having it. One thing I did think of, these three weight a staggering 70kg! Three Lithium would be much lighter, although only 100AH. So if weight was an issue, I would have probably gone to look deeper into the cost of them and the necessary upgrade.
A neighbour was the same ... She has minimal electrical needs but stays off-grid for extended times. needed good reliable batteries, but on a budget so fitted a single 200Ah lead carbon. Long warranty, no charging complications upping the cost and just does the job.£140 buys a lith 100 ah unit, but im the same as you and only do a overnight when away, i bought 2 90ah lead acids now over 10 years ago and still do lights and run a 230v small fridge for 24 hrs no bother, when they die i shall go lead carbons saving expensive units to change.