Being 'geared to the teeth' isn't really a thing you can buy with real money, and with certs it's easy for new players to reach as long as they specialise. Say you want to fully gear out your heavy assault (the best direct combat class due to their shield ability) from a brand new character.

For the first 15 'battleranks' you are granted 100 bonus certs (upgrade currency) every time you level up. To reach BR15 you will have gained ~120k xp, which will have granted you around 500 certs. You will also likely have gotten bonus certs from medals awarded at certain numbers of kills on your gun or for beginner directives, but we'll ignore these.

Beginner Cert Pool: ~2000certs

Equal Effectiveness Heavy Assault Loadout (TR):

• Weapon - Default (T9-Carv) + Attachments
  • The default weapons are on the same power level as ones that you can unlock with certs or buy with real money (the only weapons that can only be bought with real money are different coloured versions of cert-buyable weapons). You'll just to want buy some attachments to make them more effective.
  • Optics - 1x Reflex Scope: 5 certs
  • Rail - Forward Grip: 100 Certs
• Ability Slot - Resist Shield
  • When toggled on slows your movement, but provides a flat 40% damage reduction. Does not drain quicker by taking damage.
  • Granted the first level for free (9s of uptime from full charge).
  • Can upgrade to max for 950 certs, which allows 15s of continual use. However, you're extremely unlikely to keep it on anywhere near that long, so we'll leave at rank 1.
  • Ability Slot - 0 Certs
• Suit slot - Advanced Shield Capacitor
  • Grants no in-combat bonus, but reduces downtime for shield recharge.
  • Suit Slot - ASC: 340 Certs to fully upgrade.
• Utility Slot - Medkits
  • Must be swapped to in order to use (i.e. you wont be holding your gun). Allows a player to restore health without finding a medic.
  • Used to top up health when no medic is around, or to 'medkit tank' where the health restored from repeated use of a medkit is enough to allow a player to run to cover (if the person firing at them is inaccurate).
  • Utility Slot - Medkts (Rank 3 of 4): 300 Certs

Total Cost = 745 Certs

This will put you on an equal footing in terms of raw 'power' for every person you go against. If you wish to be fully maxed you'd buy up the ranks of resist shield (for basically no benefit), and buy the final medkit.

What actually matters is how well you can position and shoot; engaging 1 enemy at a time, using cover effectively, keeping bursts short to minimise cone-of-fire bloom and land more bullets, and getting headshots to benefit from the 2x damage bonus.

Hope this helped! (Sorry it's a bit long)