0. The UI takes a bit to get used to. It's a bit frustrating when starting out to interpret how far you can move in one Action Point, where you can/should drop traps, where to place guys for good lines of fire, etc. but you should pick that up pretty quickly.

1. Be ready to spend money to upgrade your weapons - you'll get outclassed and get in a bad spiral of expensive healing leading to profitless missions if you fall too far behind. And watch out - just because gear is more expensive doesn't mean it's better or fits your tactics.

2. Early on you can run up and drop a trap on them, but that only works for a little while. They get moves just like you, so having guys standing next to them, or in their attack range (most of the enemy get ranged attacks very soon) just means they can get 2 hits on your guy instead of moving, plus possibly hit him with an effect. Especially since traps DO fail, sometimes several times in a row. That can lead to expensive healing or even losing the guy.

3. It's a tactical game, think a bit and have a plan. Focus fire on the worst threats, close doors (yeah a lot of them will open doors, but it will still save you a LOT of damage), be ready to move back out of danger, but also try to be efficient in movement and placement because you only get 3 guys with 2 action points each turn, each one you waste gives the ghosts more time to do damage, split/summon, or attack you.

3a. DON'T PANIC - bad stuff will happen, you'll miss critical shots. Don't just click fire, fire, fire when that happens, stop for a second and think if there's something better to do - running a guy out of danger, hold fire on the pull weapons so you don't pull an enemy where he can wreck you, whatever.

4. Tactic to think about: there are traps that do Pain damage, even fairly early on there's one that can be upgraded to Pain 3. Having one guy with a push weapon, 1 with a pull, and have them alternate fire pushing/pulling an enemy over it can really add to your damage dealt - +3 is a lot when the weapons are only doing 5 per hit. Push/pull gives a bit of control too, you can move an enemy to a square where one of your team can shoot him without wasting a point to move, you can push away threatening enemies to hopefully at least make him use an action to come attack you.

5. Some of the mid range push/pull weapons can be upgraded to do the opposite - pull/push. So if you're looking for something specific and don't see it in the list, look at the upgrades to see if it's one of those.

6. Buying the next size vehicle/HQ is often the trigger to increase enemy difficulty. If you're getting wrecked mission after mission, maybe don't upgrade until you can get a handle on the current difficulty.

7. Check the stores right away after any objective is completed, there might be new gear. The game will notify you *some* of the time, but there's a few it doesn't do.

8. If you're having money troubles from healing, sometimes it can cost $1500+ to heal a guy - remember it only costs $150 or so to hire somebody new, pretty tempting if they have better stats eh?

9. Training can raise all the other stats, but taking Sanity damage seems to be the only way to gain Sanity - once per mission, a guy who takes damage will have +1 after he's healed.

10. When I hired, I looked for high Sanity and Aim, and after that decent carrying capacity, movement and intelligence. Intelligence gets more important later when more of the weapons/traps have minimum requirements, and the stuff does get heavier and heavier, but also those secondary stats will improve gradually as you do missions. Whereas with Aim/Sanity, if you constantly miss shots you will get your butt kicked, and if the guy can't take a sanity hit or 2 you'll get your butt kicked AND probably lose him.

11. When possible don't load guys up to their absolute weight capacity, there's various effects that will lower it and reduce them to 1 square movement. If the excess is traps you can at least place them to get rid of the weight, other gear is a lot harder, afaict you either exchange with another team member IF he can handle the weight/item stat requirements, or drop stuff off to the car if you hike back to the exit square.

12. The time to really watch your money is when there's only 1 or 2 days left before rent is due, make sure your next week's number is in the green. If it's not, just before rent is due is a good time to make sure your ectoplasm is all sold, sell obsolete weapons/traps, etc. If somebody would cost $$$$ to heal, maybe hire a new guy and leave the wounded guy at home until the new week. The week AFTER you ended a week in the red is the real danger, be super careful to make sure you'll end that week with a surplus or be ready to reload/restart. And watch the day count before doing upgrades, it's way too easy to put the next week's number in the red when buying a base, car or gear.

13. It's not crazy to have an extra trap or 2 in the car, or weapons of a different type. You can access the car if you're on the exit square, and it sucks to lose a mission when the team members with the empty traps you were planning to use panic offmap. Or there's one enemy left and it's hiding in a small room, and the only guy you have left has a weapon with a minimum range. In fact if at all possible I have any guy with the minimum range weapon carry a backup weapon with Push, if he can handle the weight.

14. Parks/cemetaries are good and bad. It's nice to have clear lines of fire for once (if you go in the daytime), but those lines go 2 ways, it's a lot easier to get swarmed and there's no doors to hide behind. Cemetaries at night are rumored to have tougher enemies too... In the parks enemies can go around the outside fence and be hard to spot, this is where a sensor can save a lot of time.

15. Starting one guy with a "count ghosts/show ghosts" sensor in hand can save turns and is a big aid to planning. 1st turn scan to get an idea of how many ghosts, ideally where they are so you don't waste turns checking empty rooms. I almost never needed to scan again after the 1st turn (except in the parks) so I usually use his 2nd AP to switch to a trap.

16. Traps aren't as sexy as weapons, but keeping up with technology helps a surprising amount. Traps that capture ghosts at a higher energy level will save a shot or 2 per ghost, higher %capture will get the job done quicker and damage your guys less when they fail less. Wide-angle can be placed to have multiple attempts if it fails or block a bottleneck better. Look at the upgrades, some of them are REALLY worth it - +2 pain to that initial 1 Pain trap, and making the wide-angle pain trap slingable are 2 I especially remember.

17. There's a link to the manual off the store page, it's somewhat helpful but leaves a fair amount out. The FAQ on their company page has some helpul stuff too: http://www.application-systems.co.uk/ghostcontrolinc/faq.html

My Loadouts,early-midgame:
Pointman: Pull weapon, pain trap
Pusher: Push weapon, pain trap, starts with sensor in hand
Long Range: Long John/Aretemis bow, throwable trap
-spares: extra throwable or wide-angle traps, some are only 1kg, can often save a turn or 2, or not risk damage to a guy by not needing to walk over and pick up a trap.

Interesting combo I saw: Stun2 gun w/cooldown 1 + non-cooldown gun in other hand
Kind of annoying not to have a trap ready, but gets to stun an enemy every other turn

Later game:
All: Stun 2 damage 11 gun, slingable Ring of Fire trap if they had the stats, some other trap if not

Didn't find a use for:
Combination weapons - added damage was too little compared to usefulness of push/pull
Explosive/forked - situational, didn't usually have that many multiple enemies near each other. By the time I did I could pretty much mow them down with regular weapons.