total (using sum())

bump, code updated.

You must have following relationships in your models

a users hasMany addresses an addrese belongsTo a user an addresse hasMany transactions a transaction belongsTo a addrese

and then for a user you can call

$user->adresses()->transactions()->sum('amount');

@StefanVoinea

These are my relationships from my models:

user model:

    public function addresses()
{
    return $this->hasMany('App\Address');
}

address model:

    public function user()
{
    return $this->belongsTo('App\User');
}

public function transactions()
{
    return $this->hasMany('App\Transaction');
}

transaction model:

    public function address()
{
    return $this->belongsTo('App\Address');
}

Now when I try to use this in my view it says:

Call to undefined method Illuminate\Database\Query\Builder::adresses()

in my view I use:

{{ Auth::user()->adresses()->transactions()->sum('amount') }}

still need help on this.

you named addresses and call adresses with one d

I'd suggest using Eloquent's hasManyThroughrelationship, since a User has many Transactions through the Address model.

// App/User.php
public transactions() {
    return $this->hasManyThrough(App\Transaction::class, App\Address::class);
}

Then, you can just do it like

Auth::user()->transactions()->sum('amount');

Much cleaner solution, since you don't have to be explicit about the Address model.