Going into transition, my two biggest problems that I was afraid of were that my family was going to reject me, and that I was going to end up unpassable and ridiculed by everyone.
It took 2 years to actually happen, but my fear about family rejection actually did unfortunately come true. My dad isn't talking to me anymore. The thing is, though, having it happen so far into transition rather than immediately has allowed me to be able to deal with it, because by the time he decided to reject me, I'd already reached a point where I couldn't even imagine going back. Going out into the world and being accepted by people as I really was gave me the self-confidence to be okay with one of the most important people in my life rejecting me, because by that time my female self wasn't even up for debate anymore as far as I was concerned, it was just who I was. Whereas pre-transition I needed all sorts of help and respect and support just to convince myself that I wasn't a horrible person for transitioning.
Surprisingly, the being-unpassable thing ended up happening too. (Although, again, it wasn't until about 8 months into being full-time at my new job that I discovered it.) And, well, again, the fact that I did experience what it felt like to just be myself unquestionably gave me the drive to get through it. I'm still working on it, because I'm still dealing with a lot of body dysphoria in regards to my appearance, but again, it's not the big deal I made it out to be pre-transition. My biggest complaint isn't that people are treating me like a freak, it's that they're being too nice to me, giving me this special-snowflake treatment.
Issues that I initially wasn't worried about which ended up happening anyway... getting fired from two jobs due to dysphoria. I NEVER expected that to happen.
Basically, if I had told my pre-transition self that I was going to get rejected by my dad, fired from two jobs due to being trans, and all to end up in a body that's still unpassable and still not female to my own judgment on a fundamental level, I NEVER would have had the courage to transition at all. But all things considered, it was more manageable than I expected. Despite some lingering personal issues with self-confidence, and lingering body dysphoria, things turned out okay in the end. Being able to experience the social freedom to be myself, and having a body that finally feels right even if it still doesn't look right, was worth it all. I realized that it's not my problem for doing what makes me happy, it's their problem for having issues with that. I had none of that attitude pre-transition. I only developed it through facing my fears and realizing that even my worst fears weren't as bad as I thought they were going to be.
In terms of other issues... I'm currently uninsured because I can't afford it, I'm using that money to save up for SRS because here in the good old US of A, you have no choice but to pay for it out of pocket, I was fired for being trans from a job in New Jersey despite there being trans-inclusive anti-discrimination laws in place because they just picked another bulls*** reason out of the blue that I couldn't challenge, so yeah, where I'm living is not a trans-friendly place. I've had to pay for EVERYTHING out of pocket, I've gotten no assistance whatsoever from our healthcare industry to deal with this medical condition, and I've lost so much because of transition that it's not even fair. America, especially the Midwest, is a s***ty place to be trans.