Sorry sl886, I did not see this topic till today.  Due to 最近天寒地凍 the desire to ML is lessen for QQ 女.  We have to work harder to get there.  I just did one over the weekend and I had to blast my heater to warm up the apartment before she is willing to disrobe.  
你怕QQ 女上到房佢先至唔制. If that is the case I suggest you should hint that she will be spending the night in a single room with you.  If she did not protest then this means she most likely will be OK, at least you will get a HJ.
培養感情 can be anything she is interested in, so you have to find out first.  天寒地凍 options are less, here is the run down that may work:
1.) For an 18 year old, you can bring her to an internet bar which is very cheap and time will go by fast.  
2.) The obvious will be "East Door" shopping which may cost you a few hundred but definitely can 培養感情.  Give her some sugegstions when she pick her clothes but must set your limit not to over spend.
3.) Follow up with "Little Fat Sheep" for hotpot and you can show her how gentleman you are by serving her.  Of course having hotpot is a good excuse to get her a few beers to get her into the mood.
Just a few suggestions, I think other c-hing can think of more.

hahaha, 發現條女只是得17嵗半(1990年8月生), but the problem is even that may be fake, she can be 16 for all we know.  Sorry I don't know about the mainland law on child molestation but gut feeling tells me to let this one go till you can confirm.  I usually eat 20+ so I have better chance to judge her age correctly and much less chance to get thrown into the slammer.  Also I have the advantage since I have my own apartment with "eat banana" guarding the lobby.

Thanks for the good report.  You already stated the problems with young QQ girl, most of them are here for quick money.  There are trade offs, obvious is 富“計”重非常非常新淨 but sometimes they are 太幼齒，唔識 num 仔.  I usually go with 20+ with better feel and so far no one asked for any money yet.  Touch wood.