Terrace property, hosted by Garry

The heat pump was installed in 2023.
The installers were onsite for a week. There were a few delays due to some minor issues, and probably could have been done in 3 days.
After the £5k grant (£7.5k now!), the heat pump installation cost about as much as installing a new gas boiler. Octopus gave a great quote, likely only covering costs (2023 install).

Separate to that, I also had solar panels, batteries and an EV charger installed around the same time. That took about 2 days.

You don't need these to have a heat pump for heating.  They do allow for reducing the cost of electricity the most by charging the batteries and using heat pump at cheap rate at night (e.g. an EV tariff), and then using the batteries to run the house and heat pump outside cheap rate. Also, the power generated from the solar panels can be used to power the house, charge the batteries and export to the grid to earn money.

Charging an EV car on cheap rate, compared to petrol, saves about £1-1.5k each year.

The cost of solar panels, batteries, and EV charger, has a payback period of about 5 years. I installed a few things which weren't really needed, which added to cost, and so payback could have been quicker (about 3 years).

It's great. House kept at about 20C all the time throughout winter. I heat all rooms now rather than keeping rarely used rooms unheated. It makes living in the house more comfortable and it is also the most efficient way to use the heat pump l.
If I just had the heat pump and was on a standard rate electricity tariff, I would be paying about the same as I was for gas/electric when on a combi boiler. However, My electricity bill over the year is very low/zero, as I use a cheap rate over night tariff to charge the batteries, and car, so never pay more than cheap rate tariff for using the heat pump, as it is run from the battery when not using the overnight cheap rate from the grid. . Also, by exporting electricity from the solar panels to the grid over the summer puts my electric bill in credit which the offsets the winter bills.
My gas supplier has been fully disconnected, as nothing in the house now used gas and I was fully reassured after one winter that the heat pump works fine through the cold months.