I am planning a 7 day trip that I am considering extending to 10 days if need be but I'd like to avoid if possible so that I don't miss much work. I work in marketing, so when I'm gone I miss a decade per day it seems. However, I am spending the money to take in the world and I'd like to do it properly. I'm 24/female. I'm planning to start in Ireland- possibly. Some have told me it would be easier to start in Rome and work Westward. Does this seem at all possible? I'd like to spend the most time in London/Paris. Also any recommendations for awesome hosts on Air BNB for these places would be great. I am also a Youtuber and plan to vlog/video my travels so should I worry about leaving my equipment in an AIR BNB and should I worry about wearing my camera around my neck?
As above, ..possible.
Why though?
You would spend most of your time in transit, and a load of money just to sit in airports and check in and out of accommodation. ...
What's the point of the trip?

I can understand trying to push as much into as short a time as possible, but have you sat down and worked out just how long you will spend travelling as opposed to the amount of time sightseeing? You also haven't made any allowance for getting over jet lag when you arrive. Even cutting to just London and Paris is still not giving you very long in either place. You could easily spend 7 days in each and still only begin to scratch the surface.

I love that you want to see the world, and that you are spending your hard earned money on travel, rather than 'things'. But I tend to agree with the other posts; why jam so much into a short trip? You will get much more out of your trip if you take your time. 4 countries in 7 days is out of the question (Ireland; UK; France; Italy) You will be traveling most of the time! Why not pick 2 that are close by, and save the other two for next trip. Ireland/London is very convenient. Only a 45 min flight between Dublin and London. ETA: you are 24 years old. The world isn't going anywhere.

It's "possible", in a literal sense, but also pointless - you'll effectively have only one day in each of your destinations (and that's assuming "Ireland" just means Dublin and "Italy" Rome).
The good news is that there are ample flights among all those destinations so doing two in a week would be very easy. Three days in city one, a day of travel, three days in city two.
Yes, Dublin-London and London-Paris are the shortest distances, but to be honest...by the time you've got to an airport, gone through security etc., the extra couple of hours for the longest flight - Dublin-Rome - will make very little difference.
I can't see why it would make much difference whether you went east-west or west-east.
Physically possible. But as London and Paris each merit a full week each, and "Italy" (the whole country?) would need months, it's daft to try - especially as it's going to take about half a day to get from destination to destination.
How can anyone here advise whether a certain Airbnb is safe?