Guide for playing Scout and Engineer on MVM
This will be broken up in multiple parts first will be team balance and upgrades/strategies. I will only be going over the 2 classes for upgrades/strategy that are very difficult without in this guide as there it would take at the very least 15,000 characters to go through all of them.
Team Balance:
So starting off with how you should balance your team. This is going to be my list in order of most needed classes:
Crucial(Very difficult without):
1: Engineer
2: Scout
Good(Can be completed without but recommended you have one):
3: Soldier
4: Medic
5: Heavy
6: Demoman
Situational(Not amazing for all maps but good for certain situations or require a lot of skill):
7: Pyro
8: Sniper
Bad(Just bad... do not choose or you will most likely be kicked):
9: Spy
What i recommend: I recommend generally having 1 of each of the top 6 classes and trading out ranks 4-6 if the situation arises where you could use them.
Don't get me wrong this isn't the be all end all. People have done very odd strategies that consist of everyone playing the same class and have won with the only exception being Spy.
Team Balance:
So starting off with how you should balance your team. This is going to be my list in order of most needed classes:
Crucial(Very difficult without):
1: Engineer
2: Scout
Good(Can be completed without but recommended you have one):
3: Soldier
4: Medic
5: Heavy
6: Demoman
Situational(Not amazing for all maps but good for certain situations or require a lot of skill):
7: Pyro
8: Sniper
Bad(Just bad... do not choose or you will most likely be kicked):
9: Spy
What i recommend: I recommend generally having 1 of each of the top 6 classes and trading out ranks 4-6 if the situation arises where you could use them.
Don't get me wrong this isn't the be all end all. People have done very odd strategies that consist of everyone playing the same class and have won with the only exception being Spy.
By playing this game you can get 100
Play
Let's move onto upgrades. I will be splitting this up into classes.
In General: You have your basic choices of resistances that go up to 75% with the exception of Critical resistance which goes up to 90%, speed/jump height that go up to 30%/60%, and health regeneration that goes up to 10 health per second. All class's weapons that deal damage can get a 200 health on kill bonus. All classes have these same upgrades with the exception of Engineer who has an extra that is Metal regeneration which goes up to 25 metal every 5 seconds.
1. Scout:
Primaries: You have the choice between multiple shotguns which do basically same thing and also have the same upgrades. Shotgun which can be upgraded for damage, clip size, reload speed, firing speed, and penetration. You have the choice of a secondary of a pistol, drink, or mad milk.
Secondaries: Pistols can be upgraded for firing speed, reload speed, and clip size, drinks can be upgraded decreased regeneration time, and mad milk can be upgraded to slow enemies and as well as also being able to be upgraded for decreased regeneration time.
Melee weapons: You have generic melee weapons which you can probably guess what you do with, the Fan of War which grants the ability for anyone to do minicrits for a few seconds on any enemy you hit, and the Sandman which allows you throw baseballs and stun enemies from a distance. All of these have the ability to be upgraded for swing speed. The only one that differs is the Sandman which you can upgrade the amount of baseballs you have as well as make those baseballs do the same as the FoW.
#1 Strategy: Upgrade resistances and movement speed to max and run around gathering money since you get a health bonus every time you grab it. It is also your primary goal. Use and upgrade your Mad Milk to the max and use but not upgrade the Fan of War to grant minicrits on Giants so your team can take them out a lot easier and faster. Use your mobility for getting things your team missed.
In General: You have your basic choices of resistances that go up to 75% with the exception of Critical resistance which goes up to 90%, speed/jump height that go up to 30%/60%, and health regeneration that goes up to 10 health per second. All class's weapons that deal damage can get a 200 health on kill bonus. All classes have these same upgrades with the exception of Engineer who has an extra that is Metal regeneration which goes up to 25 metal every 5 seconds.
1. Scout:
Primaries: You have the choice between multiple shotguns which do basically same thing and also have the same upgrades. Shotgun which can be upgraded for damage, clip size, reload speed, firing speed, and penetration. You have the choice of a secondary of a pistol, drink, or mad milk.
Secondaries: Pistols can be upgraded for firing speed, reload speed, and clip size, drinks can be upgraded decreased regeneration time, and mad milk can be upgraded to slow enemies and as well as also being able to be upgraded for decreased regeneration time.
Melee weapons: You have generic melee weapons which you can probably guess what you do with, the Fan of War which grants the ability for anyone to do minicrits for a few seconds on any enemy you hit, and the Sandman which allows you throw baseballs and stun enemies from a distance. All of these have the ability to be upgraded for swing speed. The only one that differs is the Sandman which you can upgrade the amount of baseballs you have as well as make those baseballs do the same as the FoW.
#1 Strategy: Upgrade resistances and movement speed to max and run around gathering money since you get a health bonus every time you grab it. It is also your primary goal. Use and upgrade your Mad Milk to the max and use but not upgrade the Fan of War to grant minicrits on Giants so your team can take them out a lot easier and faster. Use your mobility for getting things your team missed.
By playing this game you can get 
100
Play
100
Play
2. Engineer:
Primary: The engineer has the choice between shotguns that differ a little bit but generally do the same and can be upgraded for reload speed, fire rate, penetration, and clip size. The only exception to this rule is the Rescue Ranger which shoots projectiles that can heal your sentry and can also pick up your sentry gun from a distance.
Secondaries: You have the choice between a Pistol which can be upgraded like the Scouts Pistol, the Short Circuit which can remove projectiles from the air at the cost of it doing very little damage and can have upgraded firing speed, and the Wrangler which can allow you to take control of your sentry and shoot things that it cannot see or something you want to target specifically as well as increase the fire rate by 15%.
Melee: You have Wrench's that repair and upgrade your sentry gun. Every wrench with the exception of the Gunslinger are the same with not too major differences in them. The Gunslinger turns your Sentry gun into a Mini Sentry making it do little damage and be destroyed easily. It's essentially a joke to use it for MVM. The "best" wrench would be the Jag since it can repair your sentry faster than any other wrench. They can be upgraded for Swing speed as well.
Sentry/Dispenser/Teleporters/Metal: There are only 2 Sentries. One is the full sized Sentry and the Mini Sentry. The Mini sentry as said above is a joke for MVM. Their upgrades are the exact same. You can upgrade the health, firing speed, and even get a Mini Sentry secondary. There is only 1 type of Dispenser and Teleporter. The Dispenser gives ammo and health to you and your teammates and can only be upgraded to have more range. The Teleporter teleports you around and can be upgraded to be a two-way teleporter.
#1 Strategy: Use the Rescue Ranger as a primary, upgrade in order of Dispenser>Sentry Health>Sentry Fire> Wrench Speed>Metal capacity (to repair your sentry). Put your Dispenser near your team and let your sentry go to work on stuff.
Primary: The engineer has the choice between shotguns that differ a little bit but generally do the same and can be upgraded for reload speed, fire rate, penetration, and clip size. The only exception to this rule is the Rescue Ranger which shoots projectiles that can heal your sentry and can also pick up your sentry gun from a distance.
Secondaries: You have the choice between a Pistol which can be upgraded like the Scouts Pistol, the Short Circuit which can remove projectiles from the air at the cost of it doing very little damage and can have upgraded firing speed, and the Wrangler which can allow you to take control of your sentry and shoot things that it cannot see or something you want to target specifically as well as increase the fire rate by 15%.
Melee: You have Wrench's that repair and upgrade your sentry gun. Every wrench with the exception of the Gunslinger are the same with not too major differences in them. The Gunslinger turns your Sentry gun into a Mini Sentry making it do little damage and be destroyed easily. It's essentially a joke to use it for MVM. The "best" wrench would be the Jag since it can repair your sentry faster than any other wrench. They can be upgraded for Swing speed as well.
Sentry/Dispenser/Teleporters/Metal: There are only 2 Sentries. One is the full sized Sentry and the Mini Sentry. The Mini sentry as said above is a joke for MVM. Their upgrades are the exact same. You can upgrade the health, firing speed, and even get a Mini Sentry secondary. There is only 1 type of Dispenser and Teleporter. The Dispenser gives ammo and health to you and your teammates and can only be upgraded to have more range. The Teleporter teleports you around and can be upgraded to be a two-way teleporter.
#1 Strategy: Use the Rescue Ranger as a primary, upgrade in order of Dispenser>Sentry Health>Sentry Fire> Wrench Speed>Metal capacity (to repair your sentry). Put your Dispenser near your team and let your sentry go to work on stuff.
