Hi Dazed and Confused (perfect nickname!)
as already said, there's whether you can, and whether it fits into your life. Whether you can is up to a lender, that's your first step. From what you said, it would appear you're more than ready and capable of buying a home. You have good credit it seems, and a good rental history. The big question is a new job, and that would depend on lending guidelines and if its a new type of work for you, or just the same work for a new company. You definitely need to figure that out.
As far as the 2 year guarantee, I would definitely try to buy while you have that set income before you change to a partnership. I dont know the particulars of the partnership but it could be that a lender would not look as favorably on a new partnership, so before that change would be better.
as far as a good time to buy, I'm getting out my crystal ball now... most people agree prices aren't going up, from there, opinions abound. Will they go down a bit, will they stabilize but stay stagnant, that varies by opinion and will also vary by where you're buying. Our inner city has not gone down as much as other areas, and remained more stable. the rest of the city and outskirts vary, but that research is done as part of the buying process and a Realtor can help with that information.
with what little I know, I say you're a great candidate to at least take the first step and contact a lender. FIrst time buyers have a tendency to go to their bank. I highly recommend a local Mortgage Broker with local underwriting, or a credit union. Just my opinion.
Bottom line, take the first step to make sure the new job isn't an issue, they may want to see 6 months or more on the new job, that will be up to them. But go for it!
If you want to see what's out there, my website (link below) has a free search of neighborhoods in Portland and the suburbs so you can see what's out there that you might like. Then once you have your pre-approval in hand, you can get serious about looking, and with the current rates and availability of homes, its a great time!
Best to you,