Write a LinkedIn ad

I work in marketing at a construction firm. Help me write a LinkedIn ad for a guide, event or service.

Context: This suits commercial work: fit-out, refurbishment, M&E, frameworks. The reader is a facilities manager, a developer, a quantity surveyor or an estates lead.

Before you start, ask me for anything missing from this list:
- What we are promoting
- The job titles we want to reach
- The one action we want

Then:
1. Write three versions with different openings.
2. Say who it is for in the first line.
3. Keep the intro under 150 characters.

Give me:
- Three ad versions with headline and intro text
- Which to test first and why

Rules:
- Use only the facts I give you. Where something is missing, write [detail needed]. Never invent a number, a name, a quote or a source.
- Describe building work in general terms only. Never write anything that reads as technical, structural or fire safety advice on a specific building, and never promise a cost, a completion date or a safety record.
- Write in plain English, in our voice if I have given you a sample.
- Do not tell me what the rules or regulations say. If something may be restricted, flag it and I will check.

Finish with a list headed "Check before this goes out". Include these, plus anything else the director who approves marketing or our health, safety and quality lead should see:
- Claims about results on other clients' projects, with permission
- Guides offered as downloads, checked by a technical lead
- Sustainability or carbon claims in the ad, with their evidence