Hi @Technophobe , I presume you’re talking about the IHD (In Home Display) rather than the smart meter itself. These are designed to be left as they don’t work with another smart meter and have no bearing on your bill. 
You can check on the meter itself for readings to see that those are being used for your charges. 
If the meter readings are correct, you can check for accuracy here 

I'm meaning the smart meter itself. I have no way of knowing how long the previous owners had it. I know they said they "didn't really use it". I also note in the link you sent (thanks) OVO saying the newest smart meters are the most accurate? 

The Trio II is an IHD. 
Which smart meter do you have?

They all have to be certified to within strict limits so unless it’s very old, it’s probably within spec. The checks via the link will help to test it out. 
You should also double check your account usage to see if it’s using smart readings or estimates (even with a smart meter it’s possible that readings are being estimated)

If your meter is 1st generation then there’s a health check here

If it’s 2nd generation then try here

Where do I find which smart meter I have?

I didn't choose my username for nothing! Haha!

I wouldn't know where to start running checks, but can try. 

Can I request a new smart meter from OVO and can you explain how I find out if, despite the existing smart meter readings going through, I may still be being estimated?

Thank you everyone for your patience. I'm 71, have M.E. (horrendous info-processing challenges when fatigued) and have paid £200 this month alone as the first month on my new, small home's variable contract.

No problem. 
If you can post a photo of your meter we can try to identify it for you. 
Your online account will have a meter section and there you should find meter readings. Alongside each reading it should say; Smart, Manual or Estimated 

https://account.ovoenergy.com/meter-readings

Just another thought .. you probably should be on their Priority Services Register - take a look and sign up if not 

How do I send an attachment? I can’t see the usual symbol for that?

Yes, I’m on the register. Thanks!

At the top of the reply box, to the right there’s a symbol indicating picture. Click that and it will allow you to chose the image to upload/attach

Right. I thought so. Here goes.

Ok thanks. That’s the IHD (In Home Display). What about the smart meter itself - usually by the distribution board /fuse board 

It might look something like this 

Ok, that’s a Landis & Gyr E470 Series 3 smart meter which I believe is a second generation version (SMETS2)

It also has a date of 2019 so is fairly new

Ok, thanks. So, this model should be adequate and competent?

I think there are one or two things I need to look into like getting radiators balanced and the thermostat checked. I just get the feeling that "communication" isn't happening properly somewhere and I want to get someone in to check everything out. There have been a few things in general not done correctly by the seller and I'm trying my best to address them one at a time.

Many thanks again.

What type of heating do you have @Technophobe ? Someone here may be able to give some advice if it’s not set up properly.

It's gas central heating. A new Worcester Bosch boiler was fitted and registered to them in the Spring of this year, but there's a lack of clarity about the radiators which were bought independently online by the seller who had no paperwork for them or record of who fitted them. She said the plumber who fitted the boiler put them in "as a favour", but this is something I doubt and neighbours feel her partner put them in "D.I.Y". There are many "bodged" jobs emerging in my now six weeks in the property. There is no record of the boiler having been commissioned, no readings or signing off in the back of the handbook. A heating engineer I had in tells me this isn't necessary, may have been done online etc  Also, the seller "didn't really use" the thermostat for this new system, in place for six months. It was in a drawer. I need to get it wall-mounted. Something else I need to do is check the one year guarantee for works carried out by the boiler fitting company exists as they are not communicating with me. It's all a bit much, really and, in Scotland, you only get five days to declare any issues once in the new property before hands are legally washed of any responsibility anywhere. The move itself took such a toll on my M.E., I was three of those days in bed!

You should be able to check the boiler registration via Worcester Bosch @Technophobe 

They should have copies of any records as these are needed for the warranty 

Worcester Bosch not easy to get hold of, but they finally responded the other day. I do have this weird certificate thing from them, left by the seller, which looks like something a primary school pupil would get. It still doesn't put my mind at rest that everything has been done correctly and is in order. Is it really no longer necessary to have the readings filled in and signed at the back of the boiler manual? What would happen at first service without that information as a guide? Also, the boiler company going awol is a worry.

*boiler fitting company (plumber)

Our boiler is a Worcester Bosch and they have most things online now. I’m more used to a log of services in the manual but as you mention, they don’t seem to do that now. 
If they have a record of the boiler, they will also have a record of the installation readings. They say that this is done so that the next service is ‘easier’ but I would suggest that you make sure whoever services it are Worcester Bosch approved

So can they send me their record of the installation readings? I had an excellent heating engineer in my last home. I'll be getting him back for servicing. There's too much to distrust about anyone who was involved here, sadly. 

It will need you to make a ‘MyBosch’ account but you can check details here

https://www.worcester-bosch.co.uk/MyBosch

I'm not sure if they have full test readings but it records details of the installer and length of guarantee remaining 

Many thanks. I have an account, but the boiler is not appearing on it despite it supposedly having been registered with them and my having informed them of the change of ownership, equally to the fitter. This seems all terribly confusing. The online chat requires a wait of 30 minutes and I understand phone waits are horrendous. I’ll need to leave this meantime as it’s proving exhausting.

Keep us posted with how you get on @Technophobe, it may help other community members in a similar position. 

Thanks to all the help so far, I have found that the meter is sending daily readings. I have tried to reduce usage by putting the heating off overnight. I need to chase one or two other things the previous occupants have not done correctly. 

So, it seems the boiler installer may not have commissioned it or failed to provide Gas Safe with his report. There is no Gas Safe record of new installation at my property. Chasing all of this up. Also, previous occupants had not "used" the thermostat and I need to get it wall-mounted and properly set. These are steps in the right direction, I hope and may provide the answers to the issue. 

Not good when you have to chase this through. When you have time, it would be useful to know how you get on and if you think the forum can help again, just drop by