I have a home gym and I'm in the process of planning to move it from the spare bedroom to the basement as part of a basement remodeling project.

I have bought my equipment piecemeal over the last year. I'm in the US so no idea of UK brands. I'm also a beginner woman, so don't lift as heavy as some.

I started off with a 10 lb 1" bar and some cast iron weights that my DH had bought for himself in high school. I had some light dumbbells, some resistance bands, a TRX knock off I mounted to the wall, and a very cheap flat bench from Walmart. I also have a very old treadmill.

The first thing I bought a was a set of Powerblock dumbbells. They go from 5-50 lbs and are expandable to 90, I think. I haven't needed the heavier ones.

I next bought a power rack. I chose it off Amazon. It is fine but has some annoying features. If I had known better I may have chosen a better one when I bought it. A few months later I upgraded my bar to an Olympic size bar and purchased a set of bumpers. I chose bumpers not because I do a lot of Olympic style lifting, but because I am not very strong and wanted to get the bar the right height off the ground for deadlifts and hip thrusts, and my gym was next door to my kids' rooms and I often work out early in the morning while they sleep and I thought bumpers would be quieter. I'm not sure they would be necessary vs. cast iron if not for those issues. I do like them though.

The last things I have added are an incline bench, and storage for plates and the Powerblocks. In between I've added little things like a bar pad for hip thrusts, assorted resistance bands for assisted pull ups, etc.

I would make sure you have enough space and clearances. Even though I have a women's bar which is slightly shorter than a men's bar, I fairly often hit other stuff with the bar either while trying to move it or to do exercises. This is really annoying. I also have trouble getting far enough back to video myself to check my form.

Another thing to consider is flooring. I let my DH talk me into covering the wood floor with some sort of interlocking foam that is probably made more for a playroom situation than a gym. It is too squishy to squat and deadlift on. So I have to take out pieces of it when I do those exercises. Annoying. But it is nice for floor exercises like planks and such.

When we get the basement finished I will have a large space, 16x22 ft. I'm going to have rubber flooring installed like a commercial gym. I'd like a new rack at some point, with strap safeties and plastic inserts in the J cups. I'm going to get a second bar to leave set up for deadlifts and leave one in the rack all the time. I'm going to get mirrors installed on one of the walls, too. My equipment will clearly way exceed my ability, but who cares.

As far as places to buy things, I really like the things I've bought from Rogue and reviews suggest they have very good customer service. Not sure about their UK presence though. I have no affiliation with this site but it seems like it has thorough and thoughtful reviews, YMMV: http://www.garage-gyms.com/

Wow, that was long!

Start from the floor up. Get some horse stall mats and make a DIY lifting platform. Kinda like this one but doesn't need to be so big: https://youtu.be/3gqlfWXdWVs

Do NOT buy mats from a fitness supplier. Stall mats are the same thing but hella cheaper.

I second the horse stall mat, they are almost always on sale and they last forever.

I got most of my stuff from Rogue a few years back during a New Years package sale thing and have really enjoyed the quality. I've got a power rack, beater bar, flat bench, and various plates. I've also picked up a rower (which I love), gymnastics rings, and a dip bar.

Try for package deals if you can find a good one if not start a list of what you want and start hunting top to bottom.

Have thought about building a home gym just to save money from gym membership fees (at current rates it'd pay for itself in under a year), but my wife needs the push of a personal trainer not named Husband in order to actually work out consistently, and keeping her on would defeat a lot of the point of making a home gym. (Plus I'd have to figure out where to move a lot of stuff currently sitting in the basement.)

I have no idea if these are availbe in the UK, but I just ordered these:

https://www.amazon.com/gp/product/B01HDVZJ9A/ref=oh_aui_detailpage_o06_s00?ie=UTF8&psc=1

https://www.amazon.com/gp/product/B01M5G2PND/ref=oh_aui_detailpage_o06_s00?ie=UTF8&psc=1

https://www.amazon.com/gp/product/B000RNU280/ref=oh_aui_detailpage_o07_s00?ie=UTF8&psc=1