How do I work with auctions?

It's like this:

Starting bid: 50k
Min raise: 10k
Auto-buy: 100k

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Now imagine that a guy gives 80k TC.

If I want to buy it, I give more 20k right?

oh... I thought i add 20K to 80K...

but i cant add tc to the other person's donation right?

not donation but...ah...argh! i dont remeber...

then can i do

80+10+10(mine)=100?

Not the math problem...lol

I asked if I can add 10K in an auction when it's already 90K...

no
its 80k from a guy and 10k min raise.
can i add 10k to buy the thing?

but i have o bid 100k to get the thing right? Its confusing me...

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