Low spread does not equal low total cost. Real cost also includes commission, slippage, swap and funding fees.
Many platforms advertise zero or very low spreads, but Raw accounts may charge commission and overnight positions may incur swap.
For short-term trading, check spread plus commission plus slippage. For overnight trading, add long or short swap. Frequent funding users should also check payment fees.
Compare the same instrument, account currency and trading session. Spreads can widen around news and low liquidity, so do not rely only on minimum website spreads.
Keep real records for each platform: open price, close price, commission, swap, slippage and withdrawal fee.