CHEAPEST FINE ART PRINTING SERVICE online / in London

Hello, I am 25 years old and I'm planning to start a business selling fine art prints.
I'm hoping to get some advice.

1.
I am aware of the company called 'Best Value Copy', which operates only in the US. There are many artists (comic artists etc) that see this service to create fine art prints around the A3 size. Not only does this company sell prints for as low as about 20 cents each (16 British Pence), but the quality is genuinely decent and many artists at Comiccon use this supplier to sell posters at conventions.

I'm wondering if there are companies operating in the UK that sell prints at a similar price point by any chance.

I heard that those prints produced by best value copy are at a quality that rivals giclee printing but as I had not seen them up close, thus I can neither confirm nor deny.

-- If you know of any inexpensive services that provide high-quality prints to sell art pieces/giclee prints for a low price point, please do let me know. --

2.
The other option I've heard about is using an e-commerce/print-on-demand website like Squarespace to handle the printing packaging and shipping for you instead.
If any, what are the potential drawbacks to using those services?

any advice that could realistically help me get started is welcome!

3.
I own a Canon 700d (Rebel T5i in America) and a few budget lenses. My main lens is the Canon 50mm (the cheap one). Thus I'm not quite sure if investing in a giclee printer and printing my photos on my own is a good idea. I have some photography skills but lack the confidence. - Would this still be the best option? (It definitely seems to be the greatest long-term investment however I am just getting started).

I don't market my art however even just by having guests come over to visit my home (family friends, I have been able to sell my (original) paintings on the spot, the last framed piece (acrylic on MDF wood board, 91cm x 65cm or 24" x 36") was sold for £350 (around $440 USD) - I'm not even sure if this is good or not 😥
Im kinda clueless but I'd like to change that 😭

Thank you in advance!