Fuel is expensive outside the main towns. Fill up at Asda supermarkets where possible as they are all same low rate where ever you are. Fuel in the Highlands will be over £1.60 per litre
Agreed about the Loch Ness route, go up the west side via Drumnadrochit and stop at Castle Urquhart and do some Nessy spotting. Best time to her is just before sunset.
Car hire at ABZ is now a five minute walk turning left out of the terminal doors. Check the car with meticulous scrutiny for dents and scratches. Get the guy in the outside cabin to alter the record to reflect the truth. Use auto-europe.co.uk to book the car and insuranceforcarhire.co.uk to buy an excess policy and decline the hire car company's excess waiver policy. Hire a compact at the very least - you'll be glad of the extra acceleration if nothing else