18 Days in Scotland- Itinerary Advice

Have you booked your flights already? Is there a reason you are flying into Glasgow then taking the train to Edinburgh instead of just flying into Edinburgh? It would probably save you some time and the hassle of dragging your luggage onto a commuter train if you just flew into Edinburgh. It is a lot of driving, but it's not the same route I did so I can't comment on a lot other than I did do the drive out to Applecross, and found myself stopping at almost every opportunity to take photos so it may take you a lot longer than you think.

You might want to double check with your car rental company. We are renting a car in Inverness to drive to Skye and beyond, and our contract says we cannot take the rental on a ferry.... only drive on bridges... could be just the company we are using, but worth a check since your plans involve using a ferry.

this place might be worth a look

https://stayatalighthouse.co.uk/
So far every time we have been up its been booked

I'm a little confused by this:

April 25- ... Continue on to John O' Groats then catch 7:00 pm Scrabster ferry to Orkney Island.

April 27- ... return to Northlink Ferry at 9pm for early morning sailing.

April 28- Arrive Thurso about 8:30 AM.

This is the link to the Northlink Ferry schedules for 2017 -- http://www.northlinkferries.co.uk/timetables/. Pay attention to the Scrabster -- Stromness timetables about halfway down the page. It's only a 90 minute crossing. There is no overnight ferry between Orkney and Scrabster. It leaves Scrabster for Stromness at 0845 and 1900. It leaves Stromness for Scrabster at 0630 and 1645.

Scrabster is on the water just north of Thurso. John O'Groats is about 20 miles east of Thurso. Look it up on Google Maps or any other mapping options you have. There is a ferry from John O'Groats to Orkney -- http://www.jogferry.co.uk/Ferry.aspx -- but it appears to be walk-on only and that it runs from 1 May to 30 September. It was running when I did my trip, but I'd heard that although the crossing is shorter, it is much rougher, so I opted to spend the night in Scrabster and take the Northlink Ferry the next morning.

I took that 0845 ferry from Scrabster to Stromness in mid-May last year. A local bus arrived shortly after the ferry docked and I took it to Kirkwall. I spent 4 nights and 3 full days there. Then I flew from Kirkwall to Aberdeen.

I was a walk-on for the ferry. You can also drive on -- IF, as someone else has already mentioned, your car rental place will allow it. If not, and you drive to Thurso/Scrabster, you'll need to find a place to leave the rental car near the ferry terminal and walk on. One tip, it's a long walk from where you are likely to park to where you would walk on. Here's more information on that -- http://www.northlinkferries.co.uk/ports/scrabster/. Scroll down to the Parking at Scrabster section of the page.

Thank you all for the replies. I found a great deal flying in and out of Glasgow for about $600/pp roundtrip. It was much more expensive to fly into Edinburgh. I have yet to secure a rental car so I will definitely check the rental agreements regarding ferry travel. We have already purchased tickets on the Northland ferry and we are staying at the Mill of Eyrland on Orkney. Regarding the ferry timetable, Northlink allows you to board the boat the night before if you are taking the 6:30 AM sailing. We were able to get a cabin for two people that includes breakfast for about 65 euro. Most of the trip is planned and booked at this point.. we have some leeway after we leave Skye. Debating on giving up a day in the Oban/Glencoe area for extra time in Glasgow. We think with that much time in the country we may crave some city time- is it worth spending about 3 days in Glencoe?

Have you seen this website? here. The website gives you great resources for the drive you plan to do. We drove half of the route last year. What an amazing trip! Lots of driving but oh so beautiful! Plan on your drive taking twice as long as normal because of one track roads, sheep, and lots of places to stop! Don't let your gas tank get too low. Very few gas stations along the way. Smoo Cave was beautiful! Here is a great article worth reading here.
We rented a car in Edinburgh and returned it to Glasgow. No problem taking our car on the ferry. But maybe we didn't read the small print. We did use Auto Europe website to rent our car. They will compare prices of many car rental agency. Many on here use Auto Europe to book cars.

You'll really like the Mill of Eyrland on Orkney--we stayed there for four nights in July 2012 and had a wonderful time. Morag is a terrific hostess and lays out a great breakfast, and we really enjoyed talking with our fellow travelers around the communal table. We met an Australian retired couple, a young couple from Germany, and a family from Belgium whose teenaged daughter did most of the translating. Only drawback was the wifi was only reliable in the common room due to the mill's thick walls, but the service might have improved since then.

Also, Dunrobin Castle was our favorite manor house in the entire trip. The grounds and building were both impressive, yet compact enough not to be overwhelming, and everyone who worked there were just wonderful (we had a lovely chat with the woman arranging an enormous floral display at the base of the stairs). The falconry exhibit was a blast--get seats in the middle section and as close to the front as you can. We were in the second bench from the front, and since the front bench was left empty, the falconer parked his eagle owl there while he showed off the falcon, and the owl and I had a staring contest only three feet apart!