If you have an idea of what you'd like then it's worth looking second hand. I got a really nice one for £100 with all the bits and pieces. There were other ones that were cheaper but I wanted one which folded small.
I bought mine 2nd hand like new and was gifted another which is like new ... In a society where pushchair addiction is a huge thing now you can pick up relatively cheaply prams that are only a few months old and had little to no use ... I have a Graco Sky travel system and another carrycot/pushchair and paid less than £100!
Mothercare Xpedia, £250 for travel system including a car seat which clips on and suitable from birth. I've seen them since at £200. Really big basket and easy to steer with a decent choice of colours. Couldn't fault it. Gutted I can't adapt it to fit my second baby (DD1 15 months, DD2 due March).
2nd hand! Our nanny (nwoc) bought a second hand P&T for £50, put new tyres on it and washed all the hood liners etc. It looks brand new and will go all the way to 3-4yrs. I feel like a total mug for not even considering a second hand pram for the pfb.
I needed reversible handle, 4 wheels and lightweight. After toysrus discontinued Graco Symbio I was gutted, as I was planning to buy it - it was perfect. Anyway, after researching I found that bugaboo cameleon has these options, so decided to find second hand on gumtree or ebay. But cameleon is a bit pricey even after 3 kids, so bought bugaboo frog instead. Full set except car seat cost me £120 and the pushchair is in pretty much perfect condition. It even had maxi cosi adapters and travel bag, so the only thing I had to buy was car seat and tbf I would've bought it new anyway. The full travel system cost me £214. I have played with it for a bit already and am really pleased. It is much better than graco symbio. My advice - search on ebay and do it every day. That way you won't miss a good deal, if it should come up.