I'm not ever doing anything for anyone just for $10.Unless you have zero travel time between a hundred of these 10 dollar lawns you will not make any money. You have to factor in travel time between jobs. If it takes you 15 minutes to get to a 10 dollar job, 8 or so minutes to load and unload, and 5 minutes to cut it, you just dumped about 30 minutes into making 10 bucks.
Factor in postage, envelopes, and stuffing the envelope or credit card processing fees you now spent 30 to 40 minutes to generate 10 bucks minus an additional dollar or two. You are generating around 5 dollars in hour in revenue. Once you factor in all your expenses, direct and overhead, you are losing money to mow.
Get a fast food or retail job for half the stress at quadruple the pay.