To keep it short here is what I remember:
- pre 2000, most probably for Windows but DOS is possible (PC for sure)
- looked like C&C clone: sci-fi, very similar graphics
- I distinctly remember one building: it was a white tent with a red cross
- what was really cool about the game is that your money was transferable - if you managed to win a mission with just a handful of units you saved a lot of money and could use it in next mission (it was really cool and made you play the game efficiently, swarming was not an option!)
- You got paid after each mission and I think (but I'm not sure about it) you could earn some money between missions too (I'm not sure how though)
- the game was pretty buggy though and your units were extremely stupid (for example they wouldn't react if there were attacked by a unit with much larger range)

Any ideas?

If you want to play like Standart RTS > Total Annihilation will be good choice.
www.gog.com/game/total_anihilation_commander_pack

Check these, maybe

- This Means War
- War, Inc.
- Dark Reign
- KKND
- Total Annihilation
- Battle Commander
- Outpost 2
- Real War

That's definitely the one! Thanks a lot! I have three copies of Total Annihilation and I've completed the game many times, I wanted to get this specific title (War Inc.) but thanks for the suggestion.

Glad that I could help. I used to love that game. Despite the bugs. Maybe I should dig it out from the depths of the Internet :D... as nobody sells it legally anymore. I would buy it though if it ever came to GOG:).

I actually have this game. The only problem is that when I moved out to another country I asked a few of my friends/family members to keep my stuff (usually one box per person because I didn't want to clog one person with everything) and I made a list who had what. But it's hard to use this list if I don't know the name of a game ;) But now, thanks to you, I do and it turned out the game will be easily accessible so I'll play it soon :)

there is a pic from my copy :)
http://s3.postimg.org/jmgs5p2oi/IMG_20140422_111451.jpg

Congrats. I wonder if GOG put any effort into getting this game here. Too bad it has only 50ish votes...

Does it work on modern OSes?

Since it's a DOS game I think it's reasonable that it can be made to work with DosBox.

works perfect with dosbox for me

Whoa, but "Windows 95" is clearly visible on that picture of yours ;) So apparently that's one of those dual DOS/Win95 games, huh? Good to know that it will work :) I've already contacted my friend and he promised to drop in around 8 pm. So I just have to put something in a fridge now ;P

That's great, thanks a lot! I doubt I have a different version because I don't thing this game was released multiple times