Limit vs marketable limit on the open: deciding how many cents I'll pay

[Fairman]

In the first ten minutes I don't use plain market orders to enter. It isn't because they're evil. It's because I want to decide the maximum price I'll pay before I click, and the open is when the quote moves fastest. So I choose between a passive limit and a marketable limit with a fixed cap in cents.

## Rails
- Passive limit: I rest at my price and accept that I may not get filled. I use it when the setup lets me wait for a pullback.
- Marketable limit: the price is set a fixed number of cents through the current offer (for buys). My cap is 3 cents on liquid ETFs and 5 cents on single names over $20. If it doesn't fill inside the cap, I don't chase.
- I never cancel and re-send a marketable limit higher. One attempt, then I let it go.
- For exits on stops I accept a wider cap, because getting out matters more than a couple of cents.

## Worked example (illustrative)
09:34 ET. A $42 name breaks its premarket high at 42.50. The quote is 42.52 × 42.54. I want in on the break, so I use a marketable limit: offer 42.54 plus 5 cents, a limit of 42.59, for 300 shares.

It fills 200 at 42.55 and 100 at 42.57. That's an average of about 42.557, around 1.7 cents above the offer I saw when I clicked. Stop at 42.40. At 09:37 ET I sell half at 42.78 and trail the rest.

A second case, 09:38 ET, a different name: I send a marketable limit at offer plus 5 and it doesn't fill because the offer lifted away. I let it go. Two minutes later the name had reversed through my planned stop level. Missing that fill cost me nothing.

## Failure modes
- Sending a market order "just this once" on a fast name and paying 20+ cents over the quote.
- Resending higher and higher limits, which is chasing with extra steps.
- Using a passive limit for a breakout, then getting filled only on the failed retest.

## When to skip
- If the spread itself is wider than my cap before I click, that name isn't ready.
- During a halt resume or a news spike, I don't use marketable limits on entries. I wait.
- If my platform shows a stale quote, I can't calculate the cap, so there's no order.

Diagram: a quote ladder showing bid, offer, and the "offer + cap" line, with one arrow to "filled inside cap" and another to "not filled = let it go."