A few weeks ago a friend-of-a-friend emailed me to ask some advice as they plan a similar, but different trip to ours. I thought I'd post my response to share with others if it can be helpful.
So good to hear from you! First of all - so glad you have made the decision to travel. We are only 5 months in but have not regretted it for a second. Luckily our parents were really supportive and once we started telling people (2 months before we left) most people were on board. Those that don't really like to travel think we are crazy :) So GO FOR IT! Life is way too short to stay in jobs you hate when the whole world is out there to be explored.
Ok, so to answer your questions: we did, and still do, own a home in Wallingford. We did a two year lease for a few reasons. 1 is that we plan to be gone around 1 - 1.5 years and I didn't want to have an amazing trip and then come home to stressing about finding a job so we could pay the mortgage so we have a longer lease giving us some wiggle room when we get home to find a job and get settled before taking back all the payments. We also have both parents living in the Seattle area so we know we have a few options of places to land when we get back! We rented our house out furnished so we wouldn't have to pay for a storage spot the whole time we were gone. What the tenant didn't want we sold. But we will come home to mostly a furnished house, which was important to me. Some people doing similar trips sell everything before going, which is fine, but we want to come home and back again, so we kept most stuff. We stored clothes and nice cooking appliances in a storage shed beneath our stairs in our basement that my husband Eric built. It is screwed shut and we are trusting our tenant to not go into it! Some valuables went to my parent's house and my engagement ring and other jewelry went to a safety deposit box.
We quit our jobs in July and then spent 2 months at my cabin in the San Juan's (a place we have always loved and hated to leave after short weekends). We haven't had any visa problems but also haven't been places that really need visas. Brazil will be one that we are working on as we go (you have to send it to, or go to, an embassy). A one way ticket is the way to go! We bought one way tickets to Guatemala and then have been booking things as we go. So far it's worked out great but we are now in Buenos Aires, in their high season, and booking flights to Patagonia, and it's cost an arm and a leg because we are planning so last minute, but this is the first time we have traveled in the high season and that this has happened. So far we have been fine to plan from one day until the next. We have tried to travel on the shoulder season for lower rates and better prices - which would be something I'd recommend.
We planned to be in Central/South America for 6-8 months, then New Zealand for a few weeks, then SE Asia for 6-8 months or until we run out of money. We don't have a ticket home or even on to NZ yet. We did go home for Christmas (my dad paid for me to surprise my mom for her 60th birthday) but we weren't planning on going home at all.
So other advice I can give you: pack way less than you think you'll need. I used this site: http://www.legalnomads.com/wds#packing. When we went home for Christmas we left even more stuff and my bag is 17 pounds and Eric's 23. It makes travel days MUCH easier. is You also just realize you don't need much and laundry is super cheap to do on the road. Bring new USD with you. We left home with 2k because you can get really good rates for USD when traveling and because it's accepted everywhere. We can't speak to SE Asia yet but we have used ALL cash (we got a Chase Sapphire card with no international travel fees for the trip) but cards haven't been readily accepted and if they are they charge 4-6% to use them.
We had our travel fund that we were putting as much as we could into. But then what we have done on the road is have an ATM account that we withdraw money from that has limited funds (we transfer 2k a month into this account from the main one). This is in case our ATM card gets stolen (it already happened that they skimmed the number and stole $$). We also have a $250 withdrawal limit a day, and we get emails every time someone withdraws from our account to make sure if someone gets our card # that they can't clean us out. Also as internet can sometime be spotty, and I don't want to be online as much as I was at home, we don't have to check our statements daily. I would highly recommend doing something similar to this!
We got this awesome medicine kit from REI (similar to this one but the "world traveler" one) and then rounded it out with all the specific drugs we were advised to bring from the UW Travel Clinic. I would recommend going to see them asap to get started on all the shots you will need. Some of them took several rounds of shots and a few months in-between. Hopefully your insurance will cover some of it... Mine covered nothing and it was very expensive but Eric's covered some.
Other blogs to follow:
We also went to a Meet, Plan, Go Session in Seattle. It was when we were still pretty sure we were going to do the trip but not positive and it helped us meet others doing the same thing and get more confident behind our decision.