It's not straightforward I'm afraid. I don't recommend buying online for the first pair. If no choice, be ready to exchange if necessary e.g. don't wear it outside until you are sure you are going to keep it.

Many people on this thread have. I have personally bought 3 pairs from them.

from P. lal?

How much is a Loake 1880 there now? I've not been there in ages.

I don't need any more shoes in my rotation but now and again I feel an itch....

P. Lal Loake is cheaper than UK
that's why Loake also dont like let them sell

I don't think you need Renovateur for now. Maybe never. My time handling Barker shoes at PLal gave me the impression that the leather is quite heavily finished and therefore mostly impermeable, the leather might not be able to accept the Renovateur/Creme except wherever the finish has been scratched/worn off.

In case I am wrong and the leather is actually not as impermeable as I thought, I'd personally go for a mid brown creme.

From your photos, the leather looks like they will accept conditioner and cream as you can see the pores/grain of the leather.
It doesn't look like corrected grain leather, which has that glossy finish that will prevent it from accepting conditioners or cream.
So, good pick bro...my first GYW shoes was Barker too but it was a corrected grain.
If it was corrected grain, conditioners and creams would be useless and won't be able to mirror shine as well (I've tried lol).

The best practice for leather shoe care is to clean, condition, cream and wax every 10 wears (whole day/8-12 hours count as 1 wear).
Never wear the same shoe 2 days in a row, put natural wood shoe trees in them when not wearing and they may last you a lifetime.
YMMV.

Wow, you bought them at a great price! Have fun on your journey to achieving a mirror shine!
It may look simple on video but it really takes experience.

Cream is to nourish the leather and rejuvenate colour as it contains colour pigments (unless you buy neutral, which won't have any).
As you wear the shoes, especially lighter coloured shoes, its colour may change and get scuffed.
You can then use cream to bring them back to life like below.
You can't go wrong with Saphir, there are also other great brands like Pure Polish, Boot Black, etc, you need to try and find which one you prefer.

Well done for first try!! A toe cap with a medallion is harder to shine.
How many layers of wax you put before mirror shining?
You can try to build up the mirror shine by letting it rest 1-2 days and shine again.
Example of one of my best shines below.

Cause you're using Saphir and Pate de luxe only, a softer wax which needs more time to dry and set into the pores.
If you put on the layers too quickly, it'll all just rub around and not go into the pores.
Plus, our air very humid,  that's why leave it few hours or days to let it set and then shine again.
That's why Saphir also have the Mirror Gloss to assist or speed up the process as it contains more hard wax.
Oh and you may want to get a proper shoe tree with full heels if you want to mirror shine the heels as well.

This mirror shine I did it with Pure Polish. 😉

Wow, they turned out great. I was going to point out that the contrast in the first photo was too much.

I own 2 pairs of TLB Mallorca. Main Line and Artista. Anything specific you are looking for?

In general, am very happy with TLBs. The construction is top-notch, and the leather used is lovely. On par with my Carminas, and "fanci-er" than Loakes which is very conservative. I have no experience with Barkers to give you a more objective comparison.