61.129

Aeronautical experience for commercial pilots. I cannot figure it out. I am a private/instrument pilot with about 165hrs. I am going to build some time (say 50 hours) of Cessna-172 time to set myself up for getting my commercial single/multi engine rating this summer when school gets out.

I am trying to decide how much time I should build before I start commercial SEL training. According to the FAR's, for commercial SEL, I need:
- 250hrs of flight time, 100 PIC, 50 xc. Ok, that is easy.
Parts 3 and 4 confuse me.
(3)20hrs of training in 61.127 that includes atleast:
- 10hrs of instrument training, atleast 5hrs must be in single engine airplanes.
- 10hrs of training in an airplane with RG, flaps, and controllable pitch propeller.
- One cross country flight of atleast 2hrs in a single engine airplane in day VFR conditions, straight line distance of more than 100nm.
- One cross country flight of atleast 2hrs in a single engine airplane in night VFR conditions, straight line distance of more than 100nm.
- 3hrs in a single engine airplane in preparation for the checkride.
(4)10hrs of solo flight in single engine airplanes that includes atleast:
- One cross country flight of more than 300nm, atleast 250nm straight line distance
- 5hrs in night VFR conditions with 10 takeoffs/landings at airport with tower.


Ok, first the solo requirements (part 4). Lets say I have already met all three of these requirements (10hrs solo, 300nm flight, and 5hrs in night VFR conditions). Am I good to go, or do I have to "practice the areas of operation listed in 61.127?? In other words, do I have to wait until I start commercial training, then do this stuff, or is it ok as long as I have done it at some point in my flying life?

Now back to part 3. Say I already have 10hrs of instrument training from my instrument rating. Do I need to do this again, or am I good to go? Next question, how long does it usually take to learn to fly a RG and controllable pitch airplane? I plan to do my commercial SEL in a C-172RG. Would it be feasable to do those two 2hr cross countries and the 3 hours of checkride prep in the complex airplane while building up to 10hrs?
How many hours does it take a typical student to get a commercial single engine rating? Is 10hrs feasable, or is it usually much more (assuming you have the solo requirements out of the way before you start training)?

And I am even more confused about the commercial multi engine FAR's, but I will save that until after I find out about the single engine questions. Thanks in advance. I am going to go back to reading my Space Mission Analysis and Design book, it is less confusing than reading the FAR's!
Thanks in advance!!