If you're looking to not have to re-buy tools as you progress, I'd go for separate soldering and hot air stations.
For soldering, a high quality unit makes a big difference - if you can afford it, a new or second hand JBC, Metcal, Thermaltronics, Ersa or Hakko soldering station.
For hot air, a high quality makes less difference to the ease of use - a cheap chinese hot air station is fine to start with.