squat racks are okay if you have a spotter, but if you dont and will be training alone, i strongly suggest a power rack.
this is the 2010 model of the one i have
http://www.fitness-superstore.co.uk/power_cages/powertec_workbench_power_rack_yellow/12180_p.html
this is the 2011 model
http://www.fitness-superstore.co.uk..._workbench_power_rack_black_2011/13503_p.html
@ £450 it is expensive, but this will last you 50 years easy, bare in mind it also has dip bars, pull up/chin bars, optional lat pulley attachment (at a later stage), etc.
you get a lot more for your money and is a lot safer. this will also hold it's value extremely well, should you choose to sell at a later date.
i also recommend looking at body solid power racks or gymratz.
i think £500 - 700 for a home gym is the minimum spend really (i have spent over £4K on mine)
£300 - 450 - brand new rack (could possibly get one second hand for around £200)
£100 - second hand commercial utility bench (gumtree or ebay, make sure it is from a decent manufacturer, body solid, etc.)
£100 - second hand olympic bar and weights possibly 100kg worth
£50 - matting (will likely need more in future but 2 should be enough to start)
http://www.strengthshop.co.uk/rubber-gym-mat-6-x3-12mm-thick.html
those are currently the best value for money mats i can find in the UK, im hoping to get some more and double them up.
squat bars do have a place, but let's say you fail on a high weight rep, there is nothing to save you from being crushed if you dont have a spotter.
i strongly suggest a power rack over a set of squat stands.
also those olympic power bench things are useless, you can only do bench press with them and that's it, with a power rack you can do over 100 different exercises.