None of these appear next to a kit price, and any of them can cost more than the kit.
If the plug and socket are mounted outside the building, the specification requires the socket to be rated IP55 or better. That is rarely what is already on the wall. Fitting one is electrician work, not something the specification lets you do yourself.
This is the single most common extra, because the most obvious places to put a panel are a garden, a shed, an outbuilding or an outside wall.
Where connecting the device needs the circuit's overcurrent protection device replaced, the specification is explicit: that is work only a qualified electrician may carry out, under BS 7671 Section 551.7.2. You will not know whether you need it until someone looks.
Panels can total up to 2000 W. But above 960 W of panel capacity, manufacturers must advise you to consider a professional assessment of your existing electrical installation first. The specification notes this is precautionary, reflecting the principle that larger plug-in solar warrants extra consideration of installation suitability.
So the bigger kits carry a cost the smaller ones do not, and it is not on the box.
Only where permitted development does not cover you, which most often means a timber balcony or cladding, a listed building, or a wall fronting a highway in a conservation area. DESNZ observed that the fees and administrative burden "may be high relative to the capital cost of plug-in solar panels and the potential energy bill savings".
A planning application for a device costing a few hundred pounds rarely makes sense. Find out whether you are covered first.
Telling your network operator. A short form after the installation rather than before it, inside 28 days, carrying your name, an email address and where the device is. The department put ten minutes at the outside on the whole exercise. Nobody charges you for it.
On the day we read them, one UK retailer described the EcoFlow STREAM microinverter as fully G98 compliant and certified for connection here. Another UK retailer listed the same kit under products that are not on the register and said it cannot lawfully be plugged into a socket.
We are not going to tell you which of them is right, because we have not read that device's record on the register and a seller's compliance table is not the register. What we will tell you is that the disagreement exists, that it is about a product on sale now, and that the register is the only place it gets settled. Check the record before you pay, not after.
Paid for a socket or a circuit change? That is exactly the number nobody publishes.
This is the only way this site gets real UK numbers. We will publish ranges once we have enough of them to be worth publishing, with the date they were collected, and we will say how many they are based on. Nobody's details are published and no seller sees your message.