Picked up a second-hand Victron SmartSolar 100/20 for £45 — worth the risk?

Found one on Facebook Marketplace from a bloke clearing out a narrowboat fit-out. Looks clean, no obvious damage, and he says it's only done about 18 months of light use. Retail these go for £120-ish new so £45 seemed hard to ignore. Already running a Renogy 200W panel on the boat and just upgraded to a 100Ah Fogstar Drift LiFePO4, so having a proper MPPT controller instead of my current cheap PWM unit would make a real difference.

My main worry is there's no way to verify the cycle count or whether it's been fried at some point — I know the Victron app logs faults but he says he's already reset it. The unit powers on and shows a green light on his end, which is something, but that's about all I can test over a doorstep handover.

Has anyone actually bought secondhand Victron kit and had it go wrong on them, or is it generally solid enough that a visual check + powering on is reasonable due diligence? Wondering whether to just pull the trigger or hold out for something with a warranty.

@BPH_Boats at £45 that's practically stealing — Victron kit lasts longer than most marriages, and the Bluetooth diagnostics will tell you instantly if something's dodgy once you hook it up to VictronConnect.

ValleyCruiser | 📍 Mid Wales | ⚡ 400W / 200Ah LiFePO4

@BPH_Boats Cracking find at that price! Victron kit is genuinely built to last, so 18 months light use on a narrowboat is practically run-in.

Before committing fully, grab the serial number and check it against Victron's warranty lookup — you'll at least get a sense of manufacture date and whether it's been registered. Also worth downloading VictronConnect and pairing it up; the app will show you historical data and any logged faults, which tells you far more than a visual inspection ever could.

If it checks out clean on there, I'd say you've landed a proper bargain. Worst case scenario at £45 you've got a solid parts donor. I'd take that punt all day long.

Grabbed a second-hand SmartSolar 75/15 myself last year off eBay — similar situation, someone's abandoned van build. Still going strong.

Main thing I'd check before handing over cash: connect it to the VictronConnect app via Bluetooth. If it pairs up and shows a clean history with no fault codes, you're basically sorted. Victron's diagnostics are pretty transparent so it won't hide much.

Also worth checking the firmware version — you can update it yourself for free once you own it.

At £45 vs £120 retail, even if it needs a replacement fuse or some minor faff, you're still well ahead. Narrowboat installs tend to be looked after too — those liveaboards are usually pretty particular about their kit.

I'd do it without hesitation.

DuctTapeDave56 | 📍 West Yorkshire | ⚡ 320W / 120Ah AGM

@BPH_Boats Solid grab mate. One thing worth doing before you trust it with your batteries — download the VictronConnect app and hook up via Bluetooth straight away. Check the history tab, it'll show you total yield, number of charge cycles, any fault codes logged. Basically a full health report on the unit. If the seller was being straight about light use, the numbers should back that up. Also give the MC4 connectors and the DC terminals a proper look for any heat discolouration or corrosion — that's usually where dodgy installations cause grief. If everything checks out clean, you've done very well indeed for £45. I paid £89 for mine second-hand and thought that was a bargain! 😄

Smithy51 | 📍 Derbyshire | ⚡ 480W / 180Ah AGM

@BPH_Boats Decent score at £45, you've done well there. One thing I'd specifically check on a narrowboat unit is moisture ingress around the connectors — canal environments can be pretty unforgiving, even on "lightly used" kit. Pop the cover off if you can and have a look for any corrosion on the board or terminals. Also worth downloading the VictronConnect app straight away and pulling up the history data — it'll show you charge cycles, any fault codes logged, peak voltages etc. Tells you a lot more about how it's actually been treated than the seller's word. If it all looks clean in there, at that price you're laughing. Victron stuff is genuinely built to last.

DownsOffGrid | 📍 East Sussex | ⚡ 400W / 200Ah LiFePO4

@BPH_Boats Cracking price for a 100/20 — those things are built to last. One thing I'd add that nobody's mentioned yet: connect it to the Victron Connect app via Bluetooth before you commit to the install. You can pull up the full history data — peak voltage, charge cycles, any fault codes — and get a much clearer picture of what it's actually been through than the seller's word alone. 18 months of "light use" can mean anything. Also worth checking the firmware version; if it's outdated you can update it yourself for free, which rules out any gremlins from older software. Narrowboat kit tends to be reasonably well looked after in my experience, so I'd be cautiously optimistic. Good find either way.

Gazza24 | 📍 Staffordshire | ⚡ 560W / 200Ah LiFePO4

@BPH_Boats Nice one, that's a proper bargain. First thing I'd do is download VictronConnect and pair it via Bluetooth — the history logs will tell you a fair bit about how it's actually been used, charge cycles, any fault codes, max voltages it's seen etc. Doesn't lie like the previous owner might! Also worth checking the firmware version while you're in there and updating if needed. Victron's support for second-hand kit is decent too, the serial number will confirm manufacture date if you want to verify his "18 months" claim.

Paul1987 | 📍 Cambridgeshire | ⚡ 240W / 100Ah AGM

@BPH_Boats Nice one! Worth downloading the VictronConnect app and pairing it via Bluetooth before you commit to installing it — you can pull up the historical data and see exactly how many charge cycles it's done and whether there are any fault codes logged. Gives you a much clearer picture than just taking the seller's word for it. I did the same when I bought a secondhand MPPT last year and it told me everything I needed to know within about two minutes. Cracking bit of kit if it checks out.

Ella1974 | 📍 North Yorkshire | ⚡ 320W / 150Ah LiFePO4

@BPH_Boats One thing I'd add — ask the seller for the serial number before handing over any cash and check it on Victron's website. Stolen gear does occasionally surface on Marketplace, and you'd want to know you're not inheriting someone else's headache. Also worth asking whether he still has the original purchase receipt, as Victron's warranty is transferable in some cases. At £45 though, even without warranty it's a solid buy — I paid nearly full price for mine and it's been faultless for two years.