In house salary negotiatiations.

Man that is such an open question. Depends on the city, your skill level and the company's size or ability to pay you what you are REALLY worth to them.

I once was a business analyst that worked for $20K a year under the going rate because I was a beginner in it but once I saw the value I was giving to the company (we are talking a ROI in the millions from my projects) I asked for twice what I was making and got it easily once they knew I had other suitors.

Looking back on it I wish I would have subcontracted from the first place for 6 month contracts and renewed the compensation based on performance. I think I would have asked for bonuses based on the calculated ROI.

You can use glassdoor or similar tools to find out typical salaries for your role, and use this as negotiating proof.

Or you can figure it out the complicated way. Spreadsheet all of your planned first year initiatives and calculate out the traffic and conversions to determine a total revenue for the business that you expect your work to bring in.

Don't show this to the employer.

Bring in your list of initiatives, and walk your employer through the calculations...getting them to provide the numbers. If something seems high or low, caution, suggest and adjust but the key is to get them to agree on what is realistic.

Once you're both happy with the total revenue figure, ask what they think is a fair percentage to award you in return. That's your salary.

Consider whether this is the arrangement you really want. Working for others is dangerous. You tie up your income stream in one source. You are potentially stuck working on what they approve of and not trying things that they don't "like", even though they may not know a thing about it. And worst of all, you'll be held accountable for performance--especially to these figures you both agreed on if you're using the spreadsheet method. So be conservative. Really conservative.

I dislike working for one employer only and it may not be for you. Be very careful, investigate the character of this employer fully...find out how they've treated employees in similar roles (contract to hire) in the past...and make sure to protect your reputation.