You don't need to buy a $200 grill to make some burger in your backyard. Amazon has the top quality grills and portable products, too. Just under $30, charcoal grills will do the task. However, most of these portable grills are not exactly for big families or parties. However, they would be jus enough for 4-5 people. Check out these Amazon grills below.
Yahpetes Portable Charcoal Grill
Bond Portable Charcoal Black Kettle Grill
BNCHI Charcoal Grill Perfect Foldable Premium BBQ Grill
ISUMER Charcoal Grill Barbecue Portable BBQ