It has been suggested that my wife & I start our day tour from Keflyvik, The Golden Circle. Starting in Keflyvik would save 45 minutes
bus ride. I have also heard that tours drive through Reyklavik so there may not be any saving of time. The concern is time needed to pick up luggage & take the bus to Reyklavik where a tour could be started. Is this possible? If tours start at 8 am is that too short of
time to meet bus in Reyklavik?
So are you planning on taking the tour the day you arrive in Iceland? It would depend entirely on the arrival time of your flight. I don't think I would want to do a full day tour on a bus my first day of arrival...jet lag would be a huge factor for me and I would be asleep soon after lunch! If you wanted to start a tour from Reykjavik by 8AM you would need to land NO later than 5 AM. Doesn't sound fun to me. You would also need to factor in dropping your luggage off at your hotel for storage that day. That's a pretty tight time-line...it's at least 40 minutes from the airport to Reykjavik and you would be driving into town at "rush hour" - yes there is commuter traffic that goes into Reykjavik on weekday mornings and the highway can be jammed.
That said, Keflavik is only about 5-10 minutes from the airport so you could realistically catch a tour from there if they are offered and if your flight arrives early enough. The airport is very small and you can be through immigration and out the door in 30 - 40 minutes...not always but that's how fast I got through a few weeks ago! You can catch a taxi to Keflavik and be there in no time.
The only problem would be if you are staying in Reykjavik you would need to figure out how to get back there from Keflavik if that's where the tour ends. It's about a 40 minute drive / bus ride. A taxi will cost you about $150.
Personally, I would give myself a day to recover from jet lag, settle in to my hotel in Reykjavik, stroll the town to get oriented, and then take the tour the next day.