As you’re selling the affiliate accounts as well; if I was a buyer, I’d be wanting to see the last 3-4 months traffic patterns, rankings and income and would pay a multiple of between 6x monthly net earnings and 24x monthly net earnings. Depending of course on what I saw in the numbers.
I’d also be looking at the sustainability of traffic – so if you are a big link buyer, my thoughts would be one thing, but if all your link juice is from 6 year old domains, then I’d be more confident in your offering.