Before you go out and buy your first petrol lawnmower you must decide on the blade size. smaller sized lawns should use a 16 inch cut. this is slightly larger than your average electric mower. medium size lawns go for a 17 to 18 inch. large size lawns go for a 19. 20 .or even a 21. 22. inch. 22 inch is about the max you can go for a rotary lawnmower.
new or used. if you buy new make sure you keep your receipt and read up on reviews before you buy.
If you go for a used lawnmower its best to buy from a reputable seller or dealer. a full service with a small warranty is given from these sellers.
when you have purchased your mower make sure that there is oil in the engine as many people start up and use there mowers without checking this and blow the engine within minutes of use.
please do not put oil in the petrol as many lawnmowers are 4 stroke engines and run on petrol only. only 2 strokes use a oil mix.
Look after your lawnmower. keep it in a garage or shed not outside all year.
use fresh petrol as petrol is no good after about 3 months in a can. I do recommend using a petrol additive.
Take your time mowing your lawn. give it a high setting on your first cut and go over it a few times lowering the setting as you go.
I hope that this small guide is helpful to you and thanks for reading
(if you need any advice please contact me)