Here are some Mafia Wars Strategy updates on some recurring questions:
Q: Stamina now only costs 1 point, should I invest in it for power leveling?
A: From a raw stat point per XP ratio, sure. I figure I average 2-3 xp for each fight (depending on how lucky I get with "rallying the troops), and 2.5 or so xp:stamina is great. The problem is using stamina takes time. Even if you attack a fake account, you still can only use 1 stamina per click. Even if you spam click, it would still take forever if you have a high level of stamina. Additionally, you have to heal at the doctor when your health gets low. If you have a lot of stamina, you will have to wait at the doctor to heal again for a few minutes. While maxing out stamina sounds good on paper, it does not work as well in practice.
Q: What equipment do I need to sell to get through Moscow Episodes 3 and 4?
A: Nearly all of it! Even the stuff you will just buy back later. Note: This could change if in episode 5 or 6 there is an even higher paying job. The strategy is essentially the same though, just do that job over and over again instead of the earlier ones.
You need somewhere around 1,200,000,000 rubles to get through episodes 3 and 4 completely. Sell everything not required for the escort service job in Episode 4. Even sell the stuff you have to re-buy, because you don't want to pay the tax. You'll have to do the escort service job 1400 times (tax free) to get that many Rubles (or buy the cash with godfather points).
If you do the that job ~1700 times to collect 1,200,000,000, you will pay 6,000,000 in taxes on every single extra item you have (.5% per item * 1,200,000,000). Since you can sell an item for half it's worth (i.e. an item that costs 4,400,000 sells for 2,200,000), you really only lose half its value for selling it if you plan to rebuy it.
If you are planning on collecting 1,200,000,000 and finishing episodes 3 and 4 before episodes 5 and 6 come out, you should sell any item that does not cost more than 12,000,000 (since selling it will lose you 6,000,000 if you rebuy it) because you will save money that way.