I wouldn't completely discount the idea of doing your classroom and pool work before you go! Even in most landlocked states it is possible to find a dive shop that could finish those portions with you if you can spare a couple hours at night or on the weekend. (I'm finding more and more that many OW students have this impression that getting certified takes FOREVER - not true!) It is also possible to do your classroom portions online in many places which is a nice option (especially if you don't have a dive shop super close) and then meet up with the instructor at the pool.
If I am traveling for longer periods of time (1 week+) to somewhere I would like to dive or if I am going specifically for diving, then I will bring my own gear (except tanks/weights). If I am only going to be somewhere for a couple of days or am not quite sure how many dives I will be able to squeeze in (business trip), then I just take what I consider to be the essentials: mask, computer(s), regulator, and maybe camera. If most of your travel (and diving) is going to be business related you might find that it's not really necessary to own all of your own gear... Would you actually be able to pack all of it along with you on every trip? Are you going to have time to let the big stuff dry before having to pack up?
If I am traveling for longer periods of time (1 week+) to somewhere I would like to dive or if I am going specifically for diving, then I will bring my own gear (except tanks/weights). If I am only going to be somewhere for a couple of days or am not quite sure how many dives I will be able to squeeze in (business trip), then I just take what I consider to be the essentials: mask, computer(s), regulator, and maybe camera. If most of your travel (and diving) is going to be business related you might find that it's not really necessary to own all of your own gear... Would you actually be able to pack all of it along with you on every trip? Are you going to have time to let the big stuff dry before having to pack up?