Any tips or suggestions other than just coming up with an influence score for everyone and pitting points against eachother essentially for bidding?

I was thinking maybe that the credits to spend that they had could be extrapolated into a faux influence and spent in that manner, but then I'd need a scale in which case suggestions would be lovely

First post, hi'yall!

(Please be merciful)

I ran this adventure for my group couple of months ago.

Personally I made my players roll Influence to bid on the objects and assigned a penalty to the test depending on how many rivals wanted the same item. (For example, if Octavia Nile and Master Nonesuch were both interested in the Silver Key, the penalty would be -20. If either really wanted the exhibit, they had a point pool to make the penalty even higher.)

The players could 'play the stakes' with Commerce, Logic or some other skill to gain bonus to their roll ala Rogue Trader's Acquisitioning. Furthermore, they could spend extra money from the credit chit they got from Mar to gain further boni. (If I remember correctly the ratio was +5 for every 1000 thrones they used. Someone made a list with approximate starting bids for the auction on DH1 forum I remember using, but I can't find it at the moment.)

The players had to decide how much resources they wanted to use for each individual item before rolling and they could use scrutiny and information from earlier adventure to gauge how much opposition they would face each time. If the players lost the roll, I rolled which of the other factions won the sale.

The end result was that the players had to calculate their resources and odds very carefully, if they wanted to get the more hot items, but they also had some leeway for smaller purchases. What made things difficult that each Acolyte had their eye on an item that was important for personal reasons, but ultimately irrelevant for the mission.

... and in the end they decided that they could murderhobo their hands on the items they lost after the Auction.

I hope this helps your planning. My group enjoyed the auction, but the session dragged so late that we couldn't focus on the scheming as much as I'd have liked. I also didn't write down different NPCs motivations or wealth and just eyeballed it on the spot. What the players don't know, won't hurt them.