Corporation help (Kebir Blue)

I've only been playing for about a month. A couple questions on corporations:

1) Should I purchase goods my corporations need at any particular quality? I'm currently set to 150, figuring that will help the quality of my product, but I don't know if it improves the quality enough to make up for the cost.

2) I've got my corporations selling at 10% above quality of the product. Is this about right?

3) I've got government salaries set to 400%, corporation salaries set to 500%. Again, is this about right?

4) Is selling and buying on the local market worth it at all? Does this REALLY show up in the country score? It doesn't seem to. And if it doesn't, then boosting my common market score seems that I'm just selling my goods at low cost. Right now, most of my corps contract 15% to the local market. Should I stop doing that and let them all buy the goods they need on the world market?

I know its a lot of questions. Numbers are so you can reference easily when helping me out ;-) I really appreciate it.

1. Yes buying goods at a higher quality is good, I've been told 190 is a good quality, but feel free to tinker with it.

2. You can try to sell for much higher than that if you want. Many of the game's best players sell for 60% higher and reduce the cost by 20% per month. A safer strategy is 40% higher and reduce by 20%.

3. You want to always have your government salaries a little higher than corporation salaries because if people stop working for your government.... its not good. Many people use different salary levels, I've heard that 800 is a good number, but use 600 for corporations myself. Set the government salaries about 10% higher to make sure they are always employed.

4. I'm not with common markets, but it does indeed effect your score if you sell and buy enough. However, the contracts are not profitable. Common markets benefit you when you have a large enough common market that you are selling to other players in your market randomly and without contracts, because you get a good price and a score boost.

Hope that was helpful!

Thanks EO!
I've moved government salaries to 600, corporate to 590. Set to 40/20 on trade strategy, leaving quality of goods at 150 for now. Might bump it up as my corps start making more money

I'll look for a large common market to join, I guess. And cancel my locals.

Thanks again for the help. If anyone else wants to tell me I'm a damn fool, I'm listening

do 190 for purchase quality for corps selling on the world market ME