There are far too many unknowns to give any more suggestions.
This is the real point, we are all guessing, not only about what you already have, but what you intend to install. There are many chargers available, the ones fixed to the wall come under EV charger regulations, but the plug in type can do the same thing, but get around the rules, you can get plug in types from around 2.2 kW to 7 kW. The 2.2 kW considered as granny charger and you could be looking at over 24 hours to fully charge and use a 13 Amp outlet. But you can also get chargers that plug into a 32 amp outlet these can also give 7 kW but can be selected so when you put it on charge you select the charge rate.
There are three problems with EVSE chargers.
1) Under fault conditions will it make the car live.
2) Under fault conditions will it stop RCD protection working.
3) Can it overload the house supply and blow the incoming fuse.
There are some other considerations, like the DNO should have to give permission, we have heard with some supply types where the DNO has not given permission, and having them linked to the DNO so the DNO can reduce load when there is a high demand, but first lets look at the three point.
1) With a TT supply no real problem, and should not be a problem with TN-S although hard to be sure a supply is TN-S and not TN-C-S, with TN-C-S also sometimes called PME, if for example road works damage the supply cable the earth to the house may not be a true earth, if the car is being charged inside a garage this should not be a problem, but if charged outside some one can touch true earth and supply earth at the same time and get a shock. There are a few ways around the problem which include auto disconnection of first lives (that's line and neutral) then the earth if a test probe shows difference or if voltage goes out of the 207 to 253 volt range, or if far enough from the house make the installation TT. The installer needs to do a risk assessment and select method to be used.
2) DC can freeze a RCD specially the type AC, the type A can also freeze, but if a unit auto disconnects if it senses over 6 mA DC then type A can be used, otherwise type B is required, and type B are very expensive and not available as single module width RCBO's (RCBO is MCB and RCD combined).
3) Some units have a current transformer which goes on the incoming supply, and can auto turn down the output when it approaches a set limit.
Some of the requirements are built into the charger, and some your supply, and it depends on the make and model of charger what you need to supply, so electricians go on special courses to fit EV charge points, to ensure installed safely.
As it stands there is nothing to stop you fitting a 32 amp socket
and using a plug in 7 kW charger. The same socket could power a welding set, or other power hungry appliance, so it is not classed as an EV charging point, but can be used as one. A previous thread has details
in a garage as shown unlikely to be a problem, but if the car is charged outside then it could result in a very nasty shock.
In Wales where I live outside sockets are notifiable, but that has been removed for England, not sure about Scotland etc.
But the main thing is are you willing to take a chance? Years ago around 1992 I fitted all RCD protection because I wanted to protect my 14 year old son who had taken and passed his RAE radio exam to become a radio ham. No one said I must, but I wanted to protect him.
As to when the car can be touched by the general public, milkman, post woman, or any other caller to the house, there would need to be a court case, and having read some of the reports it is unclear who would be blamed, unlikely your insurance would cover, so likely you would be made bankrupt.
I have wondered a few times if the work is notified, would the LABC be liable? They are suppose to be responsible for site safety for any work they monitor.
But clearly paperwork is required, if you make a mistake and it is not documented as the owner your liable, so you need to show you took are reasonable steps.
An EICR may shift the blame, but would it pass? And by the time you have paid the LABC for the work, and bought all the test equipment, likely it will cost you more than using a registered EV supply installer.