Rod's right that you should think in terms of total cost over several years, rather than just purchase cost.
Rod's also right that if you are content to stay day-VMC, you'll get far more aeroplane for your money if it doesn't have a CofA. The various sub-ICAO systems (UK Permit to Fly, Irish Flight Permit...) offer more aeroplane for [over several years, running costs included] less money.
If you want to fly night/IFR, you do need a CofA - in which case in answer to your question, aeroplanes that offer 4 seats and reasonable performance and reliability, but weren't built by Piper or Cessna would include the Moraine-Saulnier Rallye, Grumman AA5 (the AA5b Tiger being the best tourer and load carrier, at a small running cost penalty over the smaller engine versions).
I have a share in an AA5a and have done a lot with that, but it's not a true 4-seater. 2.5 would be more honest, but an AA5b becomes a 3.5 seater - which is better than many PA28 variants. I also have a share in a 100hp Rollason Condor, on a Permit, which flies at 90kn for £60/hr compared to 105kn for £90/hr for the AA5 (fixed costs overall for the AA5 are around double the Condor's).
Cherokee 140s are a bargain at the moment, but a bit slow and elderly. Product support still seems to be good, and they are much cheaper to buy than a -161 (the flying school favourite) or a C172. I took a PA28-140 from Bournemouth to Prestwick and back in March, and enjoyed it - 3:50 each way including taxi time, including about an hour IMC each eay which is viable, if slightly pedestrian.
G