Having specialist tools isn’t essential but they can save a great amount of time and hassle.
You will need a Andersons ALM Manufacturing GP281 Spark Plug Spanner, 2.6×2.6×10 cm to remove spark plugs. Often spark plugs are inaccessible with a spanner and too deep for most sockets. This tool has two different sizes for different size spark plugs.
Having a Briggs & Stratton 19069 Flywheel Puller is a great idea. It will save you a lot of time attempting to remove the flywheel.
Having a Draper 13906 65 mm x 75 mm Puller helps to remove the blade adapter. I place a long bolt through the stuck adapter then attach a 2 jaw puller. This easily pulls a stuck blade boss off the crankshaft.
Using XFORT® Quick Grip Clamps, Ratchet Bar Clamps, One Handed Bar Clamp, Ideal for Fast and Easy Clamping Applications [4 inch, 4 Pack] is a great idea for clamping the starter recoil when changing the pull cord or clamping a fuel line. I use my clamps for lots of various reasons.
One tool I really like is Draper Expert 22322 Impact Screwdriver Set (12-Piece) I use my impact screwdriver for removing rusty screws, particularly from the drive belt guard. I find having the extra weight makes it a lot easier to remove these parts and it saves me time.
One of my favourite most recent purchases is a New Clarke CEW1000 Electric Impact Wrench 240v
This is one of my best ever purchases. I can remove blade bolts flywheel nuts and engine head bolts in seconds. It has never failed to undo any part as yet even on a lawnmower with a bent blade. I should have bought one a long time ago.
You will need a set of Rovtop Feeler Gauge Set 32 Blades Stainless Steel Dual Marked Metric and Imperial Gap Feeler Gauges Measuring Tool for setting the correct gap for the valves and the correct gap for the spark plug.