Oh, I looooove cleaning products! I like cleaning products the way some women love shoes or nail polish.
I used to be a lab tech at Proctor & Gamble's headquarters in Cincinnati, and I was so impressed by what I saw there in terms of product development (seriously, that place was totally fascinating) that I bought stock in the company and I tend to use P&G products in my own home.
I love Fairy (although I hear that Aldi's liquid is slightly better and significantly cheaper). I also love "Flash" - but I'm really only crazy about the bathroom cleaning spray. I love how you can just feel the soap scum dissolving under the cloth as you wipe.
However, supermarket stuff is too expensive for me to use professionally. I can go through several bottles of stuff a week. I still haven't found anything I like as much as Flash Bathroom but I'm going to try.
I like Cillit Bang for kitchens - it cuts through grease well. However, I have bought a professional product that is highly concentrated and has a very high pH so it should be really good as a degreaser. It's about £8 for 5 litres and dilutes something like 20 ml per liter of water, so I think that's 250 litres of degreaser. It can be more or less dilute depending on how tough the job is.
The professional stuff I buy is called Jangro. There's a warehouse/distributor near me, and that's why I buy their stuff. I'm sure there are other manufacturers that are as good, but they're close, they have decent prices, and I like their catalog/web site because I like to look up the chemical product info of what I'm buying.
For cleaning soap scum in showers, I use a thick gel called "Washroom descaler and cleaner." It's very highly acidic. I only use it when showers have a lot of build-up on them.
I also got a neutral general cleaner that comes in 5 liter jugs for about £8. It dilutes something like 50ml per 5 liters, so I think it makes something like 250 liters of general cleaner. You can make it more concentrated for dirtier jobs. I use this instead of that Flash general/floor cleaner that comes in big jugs. It's also good for cleaning windows, at a very low concentration.
Window cleaner is something I just love as a general hard surface cleaner, but it's bloody expensive. Concentrated windscreen cleaner is much cheaper. But, I'm just going to use the general cleaner mentioned above.
I like Bar Keeper's Friend for when I want to scrub with a paste. I never use ... um, what is it called in this country? Those scouring powders that you shake out of a can. To much trouble to rinse off. But, BKF is good for stained sinks and suchlike.
I've been told that a general cheap cream cleaner is good for stainless steel (the bane of my existence) and I am going to give that a try.
Ever tried Star Drops? It's a good, general cheap cleaner that pretty much does everything. I won't use it professionally because of the cost, but I have a bottle under my sink.