I have a drive that is approx 5m by 10m and is on a slight slope towards the house (probably around a 0.5-1 m slope along the 10 m length) At the moment the drive is just old tarmac that is breaking up. Am i ok to put gravel onto the old tarmac? I am told that driving onto the gravel will cause problems as the stones will keep shifting. Is there anything else i should look out for? I am also considering putting crazy paving down...is this still classed as "old fashioned", and will it be a down point when we come to sell?