Ok, so for the first 6 months, baby should theoretically always sleep in the same room as you. So a Moses basket can be moved from room to room. My daughter went into her cot at about. 4 months I think when she out grew her Moses basket. This time I am planning on getting a co sleeper cot because despite being so anti co sleeping, I ended up doing it out of desperation so planning on doing it as safely as possible instead of waiting to be desperate.
A pram system will probably be the biggest purchase and requires the most research and time. You need to see them and try them out in a shop and think about your local area and terrain etc. No point having a big off-roader if you live in central London and are going to be on and off buses/tube, even if the pattern is pretty. I didn't get a carry cot because they seemed a waste of money, but totally personal choice.
Car seats that fit onto the pram are useful but they shouldn't be in the car seat too much as although it's the best position for car safety, it's not best for them general. So something to consider. You also need to see what car seats fit your car, how long they last and what car seat you are going to want next. It's totally overwhelming at first but we found babies R us to be really friendly and helpful as well as being the most competitive on prices