Let's try to break it down:
1) Regular Coffer: around $2650
2) Regular Bow: around $2200 (??)
3) Wallet Miu Miu: $500
4) Small Miu Miu accessories: around $600 - $700?
5) Couple pairs of Miu Miu shoes: $1000
That's around $7,050 just for Miu Miu.
3)
Prada Gauffre: $3000 (nappa version)
4) Couple pairs of Prada shoes: $1000
5) Nylon Prada bag: $1000
6) Wallets: $500
7) Make up pouches, small accessories: $500
8) Some clothes: $1500
Around $7,500
I know Prada also sells socks and underwear. Let's throw in some of these items.
So $20K is possible if all the gals in Singapore organize a buying spree. However, is it really worth it?
I mean, the discount is only valid for one season (or 1 year???) and at 10% only.
The prices are already higher to begin with and sure, you do get VIP access with sales and stuff but do you really want to purchase full-price to begin with? If you really want an item, why not?
If not, it may make sense to buy
1) while you are on vacation
2) ask somebody to buy on your behalf if they travel
3) order from another Miu Miu boutique overseas (check shipping and custom duties first)