Nice boat, but boats go by hours on the engine, not miles. If it has 150 hours, that may be a lot for a 2008. I have a 2008 Q7i with about 50 hours on it. As far as the price, sounds like it's reasonable but you should check nadaguides.com to obtain value of the boat with any options. Pulling a tube and skiers should not be a problem at all for this boat and I would highly consider getting trim tabs and a good prop. The number of people or combined weight on the boat is regulated by the sticker on the boat of what your capacities are. It should be attached below the throttle. Check for any hull damage, cracks in the gel coat, fluid leaks in engine compartment and ask for service records to make sure it's been regularly serviced. Good luck!