Figured I'd post a home brew system I've worked up for how to "buy" contacts. This is just a mechanic for buying people and making sure they stay in your pocket.
Bribery:
Tha basic value of "buy someone" works as follows: The base value is 10,000 times every level the person would be as a contact. The maintance is what you must give every month to keep the bought person loyal and is equal to 10% of the bought cost. If they miss 3 payments they must rebuy the contact.. Needless to say some people just can't be bought and some people are much easier so the GM can adjust the base value.
So here a table:
LVL1: 10,000 with a maintance fee of 1000 a month
LVL2: 20,000 with a maintance fee of 2000 a month
LVL3: 30,000 with a maintance fee of 3000 a month
LVL4: 40,000 with a maintance fee of 4000 a month
LVL5: 50,000 with a maintance fee of 5000 a month
LVL6: 60,000 with a maintance fee of 6000 a month
So if you want to bribe a border guard(lvl3) with the intent of keeping him bought it would be 30,000 as an icebreaker and then 3,000 per month. That means that you can just wiz through his guard station while he is there. But miss out on a few payments and you might get your cargo impounded to send a message.