A 180 might be a good "all around" lens, and would be a good starting point, maybe slightly short for portraits though. My favorite for 4x5 is 210, for studio work it gives you a nice working distance, and works well in the field too when you want a selective point of view. But, as stated much depends on whether your taste runs to wide or long.

When you get into large formats it's easier to think in terms of image size and angle of view rather than "wide angle" or "telephoto". It amounts to the same thing though.

Processing in trays is easy if you don't mind being in the dark for the processing time. Otherwise, you have the "taco" method in roll film tanks, Jobo reels and tank, or the HP Combi Plan tank, not to mention BTZ tubes. My preference is hangers in deep tanks which is not a method that finds a lot of favor here, but it's what I'm used to.

4x5 enlargers are easy to find cheaply if you'e willing to invest some patience for the right one to come your way via Craigslist or ebay local pick up auctions.