To sharpen them secure in a table vise. Now attach the blade sharpener to the end of your power drill. Make sure to wear eye protection and work gloves. Carefully use the sharpener to hone the cutting edges of your blades. Go slowly at first to get the feel of the best angle for meeting the blade and sharpener.
I know that many people prefer to hose their mowers down with a garden hose. I admit I have done it. Still doing that is risky. If water gets into the wiring air filter or engine you could really do some damage. Hand washing with damp rag is a drag but also your safest bet.
The Honda HRX217VKA is at or near the top of all of the expert best lawn mower lists including Popular Mechanics Top Ten Reviews and Lawn Mower Review. The testers at Consumer Reports gave this model top ratings for handling bagging and mulching and “very good” ratings for ease of use and side discharging. Additionally the reviewer estimated the breakage rate by the fourth year of ownership to be 16% which is well below any of the other mowers they tested.