I will be staying in a uk property , with no internet, for around two weeks over Christmas. It is in a built up area and previously had service from BT. TV is Wi-Fi compatible. We will have our Spanish mobiles with limited roaming data. One is new enough to support an eSIM ( I believe).

What would be a good solution for some temporary one off internet to stream some TV and also surf the web with a desktop? Some years ago , we used BT fon for surfing when staying at an elderly relatives without internet.

Could you not get a Mi-Fi unit and a data sim?

E-sim. Mu daughter does that when she travels.
They are very easy to use.
Once the plane is on the ground you switch on your phone and head to the app, fire it up and the sim is live.
She lives in Oz and has done this in various places and will do the same when she is in the UK for a couple of weeks next year. They will be flying here to visit us after and she has added spain to the e-sim and will just activate it when she lands..

When we were in Oz last year for the six weeks we had real sims and it was a faf to fire them up and then they ran out a week before we came home as it was a monthly service, we waited a week for them to be delivered as well.

Alternative is contact your current provider and ask for a data lift for a month.
We have Lobster and you can change data month by month (you get free calls in the Uk anyway on this).

Australia has always been odd over its sim cards!

UK is much easier, if the OP wants a "real" sim - can buy them in numerous places here, including airports & supermarkets, and activate within minutes

Yeah, ID check straight away... though luckily the cellphone operators are a lot more advanced than banks are at making the process as streamlined as possible. But you can get the cards anywhere, no need to wait a week for them to arrive - just visit the local Coles/Woolies and throw one in the basket.

As far as the UK is concerned just get a Lyca SIM, select a plan with LOADS of data, and create a personal hotspot for everyone to use. Lyca does allow you to get an eSIM and since they're now on the EE network their service is actually quite decent for a change...

Just be aware that loads of data doesnt always equal loads of speed, a lot of SIM only/esim plans are speed throttled, some will struggle with TV streaming.

Ain't that the truth! I remember my first few weeks back home, couldn't believe the speeds after Brisbane!!

Good point. Lyca were awful when they used the O2 network, but since they switched to EE I've never had any issues with them. I think the only other network that does prepaid eSIMs is Vodafone so they might also be worth a look in case of any "double data" promos for new users.

Do you remember when Vodafone offered something along the lines of free data on weekends for prepaid users and literally everybody thought the network would crash? And yet it stood strong (at least in the Gold Coast!) and continued to deliver solid speeds throughout the day...

I remember the wifi at work (Qld Govt) being locked down by a triple layer of passwords, only issued if they could kill you afterwards ( ) - not because of any security issues, but because there was a firm belief that no wifi could cope with more than about 20users at a time - and that was only just before covid

Edited to add, having thought back to those days, I also remember a conversation with a senior public servant who was of the impression that if internet access had been limited to Australian websites, then Covid would not have reached Australia. It was apparently the fault of us "foreigners" for talking online to friends at home........

Wow! Panic with bandwidth was prevalent back then but I never thought it applied to wifi - I figured it was only about cellphone networks not being able to cope! My oh my, maybe they were skimping on hardware and only had the equivalent of a prehistoric home router in place?

He could have saved the country a lot of hassle by implementing his theories - this way international travel could have continued as usual and the only thing that needed to be done is that country-wide internet filter to block all international communications. Overlooked genius! He should look at moving to the US - "experts" like him will be in high demand soon!