selling 2k YAC for 20LTC/1k YAC.
This annuls my previous offer which didn't even make it into the spreadsheet.

Considering my new status I'm happy to trade in small rounds (e.g. 100 YAC at once) or use an escrow.

I'd like to sell 2k YAC (18 LTC/1k YAC).

I am very new to the forum and buying/selling on here. How do people make sure they don't become a victim to a scammer? What is the accepted method?
For example:
1) escrow (but who to trust to do the escrow?)
2) split up in smaller quantities (e.h. 100 YAC) and exchange the full amount in rounds
3) just risk a trade based on reputation (but I'm a newbie for example)
4) get an authentic email or other contact info (e.g. email from work where you can tell first/last name; ebay account etc.)?

I'd prefer 1) or 2); I might accept 3) if I can verify your reputation.

Ok, this might be slightly besides the OP's question, but still: your 7970 shouldn't draw that much power! It should draw maybe 250W max? The motherboard + CPU is usually around 60-70W if the CPU idles and won't go above 150-200W on full CPU load. So in total you'd be at 320W. I'm running 4x7950 + Celeron + i7 3930k on two PSUs (gold efficiency) and I measure a mere 850 Watt from the wall socket if the CPUs idle. It was always <1000W even without optimisations. I'm only hitting 1KW if I mine YACoin on an overclocked i7 3930k as well.

A few other remarks:
overclocking increases MH/s but at the expense of a (much) higher power draw and possibly higher wear. It might not be worth it to go too high.
The power supply unit's efficiency is crucial and pays off quite quickly. A PSU with an efficiency of 90% vs. 80% makes a difference of 35-50W for you. This adds up to 5-7$/month. A multi-GPU configuration requires a good PSU anyways and the step up to Gold or Platinum standard can be viable if you plan on running it 5 months or more.

The address is in the middle of a residential area in one of the not-so-nice buildings. I would be extremely careful.

I doubt that you can simply "source" an ASIC chip and assemble a board with it. The latter step still takes a lot of knowledge. It is unlikely that someone does that in his backyard.

Alternatively, find someone in the forum who lives closeby so they can ring and see who's there...

I'm mining it too.
It's actually a pretty good stress test for my i7 3930k @3.8GHz - I get temps similar to the Prime95 benchmark.

Regarding mining: my experience was that it takes quite a lot of time till they are credited, so it might be worth waiting a bit to see if you get some.

Does anybody know how to display the current local hashrate?
And also, what is the networks total hashrate? It seems to get really difficult to min in the last hour!

Yes, I've never seen so many scam pools as for FTC and CNC.

Is there any website or any better way to find scam pools than to search on the forums?
I think there should be a meta-website that collects info on mined vs. paid out etc.
Or maybe even a "test" site that signs up to all pools, mines a bit and checks whether payouts are reasonable.

I had bad experiences with
http://chn.mnlan.net/  (payout very low, probably 10% of mined)
http://chn.ub3rl3[Suspicious link removed]m/ (payout very low, probably 10% of mined)
https://www.multipool.in/ (shows nice estimates, but does not pay out)

So what kind of settings are you using? Have you tried anything like this:

cgminer -I 7 -v 1 -w 256 -o stratum+tcp://mint.bitminter.com:8332 -u pool.worker.name -p password

Obviously you need to sign up to a pool (in the example bitminter.com) and replace pool.worker.name and password to whatever you chose.