Wanting is not valuing
Wanting happens fast, usually in the first few seconds. Valuing is what survives comparing it, sleeping on it, and adding up what owning it actually costs over a year.
Most regretted purchases are not stupid. They are a want that never got tested.
Your taste has a shape
Where Venus sits can describe what you reliably pay a premium for. Newness, quality, how something looks, how useful it is, what it signals to other people, or how comfortable it makes you feel.
Most people have one they overpay for and one they underspend on. Neither is a problem until the two get swapped by mistake, and you buy the expensive version of the thing you never actually cared about.
Pressure turns the volume up
When a planet moves across your Venus, one of two things usually happens. Wanting gets louder and everything looks appealing, or you look at what you already own and go off all of it at once.
Both feel like clarity. Neither of them moves the price of anything.
Where it becomes security
Venus decides what you want. The second house decides what happens after you have it, which is ownership, upkeep, and whether it made you feel any safer.
That is the part people skip. A purchase that solves a feeling for one afternoon is a different purchase from one that changes your position.
One question
What is this purchase meant to fix, and will it still fix it in a week?
If you cannot name what it is fixing, that is the answer. If you can, and the answer survives a week, buy it without guilt.