@Sean Dyer - one thing to consider is that whilst organic rankings are usually the best way to go and for the average small window cleaner they can be very effective,.. this type of optimisation works best on websites with 5 or 6 pages minimum, where your site is currently a bit short on content.
Still - it'd be a lot cheaper in the long run to get a new website than to spend £200 every month to boost the old one!