You say it's not a good idea to leave a car standing for six months but so long as you store it properly and disconnect the battery, or ideally connect a trickle charger, there should be no major problems. A good idea would be to get some axle stands and leave the wheels off the ground while you're away, though, to prevent flat spots on the tyres. When you return to it, check all the fluids carefully before restarting the engine and check the tyre pressures, then drive gently for the first few miles to clear any corrosion off the brake discs. We'd recommend a simple car with a good reliability record for this purpose - a Hyundai i10, Kia Picanto or Toyota Yaris would be a sensible choice.