Yesterday was training ground (TG) upgrade day with -45% on upgrades. A lot of people were waiting for it, I was one of them. I could finally upgrade my last two grounds to Q4 for maximum strength.
Except I couldn't, I had bought a training contract (TC) a few days before and I was missing 26 golds to upgrade my last TG (the horror).
I bought my 10 daily golds on the monetary market, but now I was still missing 16 golds and I had reached the daily limit of 10 gold for monetary market/donation. Guess I was out of luck, either had to buy gold with real money or wait for the next TG upgrade discount.
That's when my MU friends came out and told me about this trick I didn't realise I could use: I could sell a Q1 weapons factory for 11 golds (the maximum allowed) and dissolve an aluminium mine for 5 golds. I lost two companies (good riddance, I don't produce weapons anyway), but I got my 16 golds and now, all my TG are upgraded to the max. \o/
I now finally have all TG upgraded for maximum powaah!
TLDR: if you're ever out of gold, you've reached the daily donation limit and someone is still willing to give you gold, you can sell them one of your companies (unassign it first so they don't have to create a holding at the same place).
Hope some of you learned something today, feel free to boost for the 25 comments achievement. Happy new year and have fun!