Hi Simmo,
I asked a similar question myself and received many differing answers, here are the most common answers I had;
1 (from an accountant) 3 years net profit so you could ask $180,000 based on your figures ($5000 per month profit)
2. From webmasters 6 Months net profit is their perceived valuation of an existing website therefore you would expect $30,000 for your website.
3. a more realistic figure was a general one of 1 years net profit ( based on the pervious years income) therefore you could ask $60,000 for your website
I hope this confuses you!!
Everything is relative Simmo it depends on;
1. How badly the buyer wants your site
2. How badly you need to sell
3. How much you value it at yourself ( thats the most important one)
4. How much the buyer wants to pay for it.
I would imagine its better to hang onto your site and build it up, it would then be a long term investment and provide a steady income ( although a fluctuating one)
I have seen recently people selling websites ( or offering them for sale) at silly prices but you have to ask
1. why do they want to sell it
2. how much do I value it at.
If I was you Simmo I would ask the buyer for $100,000 then haggle!!
EDIT- Just realised your domain name “oggs” you may find the buyer wants it for the name not the content!