If you are using pure wax, i.e. non-abrasive content wax, be it synthetic (i.e. sealant) or natural wax (i.e. carnauba wax), then as KrisMas bro has said, you can do it as often as you like.

If you accidentally trap hard particle between the applicator foam pad and your paint surface, then yes it can create scratch, I think this is common sense though. Just be caution.

As for time of application in between each wax session, it is highly subjective and on a case by case basic. Assuming you referring to a daily driver, drive around Klang Valley, park in outside more than 50% of the time. Wash weekly using good quality shampoo. Clay before wax. In between wash you do not boost the wax with spray wax or quik detailer, I will say as a rule of thumb for pure carnauba wax at most one month, for sealant, maybe 3 months (depend on brand).

Easiest way of determining whether you need a new layer of wax application is to observe water beading. If it has deteriorated to a level you feel unsatisfactory even after a wash, then re-apply. Overkill is completely fine. 
Nevertheless, lost of water beading effect to naked eyes does not necessary equals to lost of wax layer existence and wax protection. To confirm on existence of wax layer on top of paint surface, you need to perform at least what Meguiar's call Squeak Test.

Ever consider invest into a portable halogen lamp stand?

inside the styrofoam box is a pressure washer? You wrap it as something precious inside. 

Today's rain is an LSP KILLER!!! Beading on MY WHOLE car just went flat...including vertical panels too....    

I have been keeping a close watch on this polisher.

bro acefreakz here has one and I am still waiting him to feedback to me some questions on the polisher such as validity of soft start and cruise control feature.

But from The Detailing World forum, Clean Your Car selling it and they comment it is a good polisher given the price tag.

You got any more infor?

you and me should give more pressure to bro acefreakz for his user infor. 
I tell you what I know:

1) Malaysia has distributor of this machine but is in Sabah however if you buy from them shipping is included.
2) Machine use standard 5/16" thread so many backing plate can be used.
3) Only side handle, no D handle.
4) I called the distributor, they claim the machine as stated in their website, has soft start and cruise control. Clean Your Car web also claim the same thing so I think is true just do not know how effective they are. So far the only normal DA (excluding Flex 3401 and Rupes bigfoot) with soft start and cruise control is the Meguiar's G220V2.
5) Made in China.
6) Thailand has one distributor too and selling at least RM100 cheaper than Malaysia distributor. But due to agreement, Thailand distributor cannot ship to Malaysia. So if you travel to Thailand, buy at there is cheaper.

thanks to my friend letting me to try menzerna power finish po 203 on the metallic black bonnet, reason for choosing her car? well because it's heavy swirls and scratches hahahahaahhaa

before:


after:


well obviously it's nothing close to perfection lol. do i need deeper cutting polish? Am using a red cutting pad from forgot-what-brand lol.

menzerna is my 2nd polish other than meg's, so i wil just compare based on the two =P plz excuse me for my noob observation if any
- menz seriously low dust
- menz do not produce holograms, as i experienced from meg's ultimate compound
- glosiness wise... mmm maybe the same? i don't notice the different from my eyes xD maybe i should do a side by side comparison nx time hehe

for bro scoutfai, the shine-mate ERO 600 polisher has soft start, cruise control wise, i noticed a some reduce in power when i pressure it too much, for medium to light pressure, it's quite consistent.

The ultimate idiot proof paint care guide for anyone new into this hobby:

Meguiar's 5 steps paint care cycle!http://www.meguiarsonline.com/forums/showthread.php?37320-Meguiar-s-5-Step-Paint-Care-Cycle-Updated!