The trade you are making
A personal account gives you complete freedom and whatever size your own capital allows. A funded account gives you size far beyond your capital and takes the freedom away. Everything else is detail.
If you have €50,000 to trade and want €3,000 a month, you do not need a prop firm — you need a 6% monthly return, which the rules of a funded account would make harder rather than easier. If you have €2,000 and want the same income, no realistic return gets you there, and access to a $100,000 account genuinely changes what is possible.
Capital access
This is the entire case for the model. A $155 evaluation that leads to a $100,000 account is offering leverage on your skill that no broker provides on your capital. Even after the profit split, 80% of the return on $100,000 dwarfs 100% of the return on $2,000.
The catch is that you only reach it by passing, and most people do not pass on the first attempt. Budget accordingly — see the true cost guide.
Rules
On your own account, a 15% drawdown is a bad month. On a funded account it is the end of the account. Daily loss limits, consistency requirements, news restrictions and minimum trading days all constrain strategies that would be perfectly viable with your own money.
Some strategies survive this comfortably: intraday systems with tight, consistent risk and a decent hit rate. Others do not: anything that needs to hold through wide adverse excursions, anything that makes most of its money in a handful of sessions a year, anything that scales into losers.
Cost
A personal account costs you spread, commission and your own capital at risk. A funded account costs you an evaluation fee per attempt, possibly an activation fee, possibly monthly platform and data fees, plus the profit share.
The evaluation fee is certain and paid up front. The profit share is contingent. Traders comparing "80% split" against "100% of my own profit" usually forget that the 80% applies to a much larger base.
Psychology
This cuts both ways and it is worth being honest about which type you are.
Some traders are saved by external rules. A hard daily loss limit stops the revenge-trading spiral that would otherwise cost them three times as much on a personal account. For them, the rules are a feature they would not impose on themselves.
Others trade materially worse under observation. Knowing that one bad session ends the account produces small, timid position sizes, early exits and missed setups — a strategy that worked on a personal account quietly stops working. If that is you, the answer is a smaller funded account, not more discipline.
Tax and legal status
On a personal account you are trading your own capital and the tax treatment is whatever your country applies to investment or trading income. On a funded account you are typically an independent contractor receiving a performance fee, which in many countries is ordinary income, and there is usually no employment relationship at all.
The details differ everywhere and this is not tax advice — see taxes on funded trading income for what to ask an accountant.
A reasonable rule of thumb
Use a prop firm if your strategy is already profitable at small size, your worst historical losing run fits comfortably inside the firm's drawdown, and your own capital is the binding constraint on your income. Otherwise, fix the strategy or add capital first — the evaluation fee is an expensive way to discover a problem you could have found for free.