* [Define] modelos iniciales.

* [Establece] relaciones entre modelos.

app/Models/Company.php

@@ -0,0 +1,9 @@
+<?php
+ 
+namespace App\Models;
+ 
+use Illuminate\Database\Eloquent\Model;
+ 
+class Company extends Model {
+  //
+}

app/Models/Price.php

@@ -0,0 +1,9 @@
+<?php
+ 
+namespace App\Models;
+ 
+use Illuminate\Database\Eloquent\Model;
+ 
+class Price extends Model {
+  //
+}

app/Models/Student.php

@@ -0,0 +1,14 @@
+<?php
+ 
+namespace App\Models;
+ 
+use Illuminate\Database\Eloquent\Model;
+ 
+class Student extends Model {
+  /**
+   * Establece la relación Students-Company
+   */
+  public function company() {
+    return $this->belongsTo(Company::class);
+  }
+}

app/Models/Subscription.php

@@ -0,0 +1,21 @@
+<?php
+ 
+namespace App\Models;
+ 
+use Illuminate\Database\Eloquent\Model;
+ 
+class Subscription extends Model {
+  /**
+   * Establece la relación Subscriptions-Students
+   */
+  public function student() {
+    return $this->belongsTo(Student::class);
+  }
+
+  /**
+   * Establece la relación Subscriptions-Prices
+   */
+  public function price() {
+    return $this->belongsTo(Price::class);
+  }
+}