We recommend searching on Etsy.com . There's some really cool costumes on there, and you're mostly supporting small businesses.
Watch: A Knight's Tale The Princess Bride The Lord of the Rings
It certainly doesn't have to be! A few choice items can go a long ways, and still be cheaper than a suit or dress.
Check out this chainmail shirt for $50 https://www.etsy.com/listing/1053035873/aluminum-butted-chainmail-half-sleeve?ga_order=most_relevant&ga_search_type=all&ga_view_type=gallery&ga_search_query=chain+mail&ref=sr_gallery-1-1&pro=1&frs=1&edd=1&organic_search_click=1 Here's a tunic for $30-50 https://www.etsy.com/listing/1328292495/medieval-renaissance-gothic-armor-viking?ga_order=most_relevant&ga_search_type=all&ga_view_type=gallery&ga_search_query=fantasy+costume&ref=sr_gallery-1-8&pro=1&frs=1&edd=1&organic_search_click=1 There's also robes for about $30-40 https://www.etsy.com/listing/1085474970/medieval-european-robe-ancient-fantasy?ga_order=most_relevant&ga_search_type=all&ga_view_type=gallery&ga_search_query=fantasy+garb+men&ref=sr_gallery-1-4&pro=1&frs=1&edd=1&organic_search_click=1
This Fantasy Dress is only $55 https://www.etsy.com/listing/1346666169/fantasy-dress-unique-design-elven-dress?ga_order=most_relevant&ga_search_type=all&ga_view_type=gallery&ga_search_query=fantasy+wedding&ref=sr_gallery-1-1&frs=1&edd=1&organic_search_click=1 A full dress costume for $60 (Currently) https://www.etsy.com/listing/1329763285/renaissance-long-sleeve-maxi-dress?ga_order=most_relevant&ga_search_type=all&ga_view_type=gallery&ga_search_query=renaissance+wedding&ref=sr_gallery-1-14&pro=1&frs=1&edd=1&organic_search_click=1 Another Dress for $60 https://www.etsy.com/listing/1052666038/irish-boho-peasant-renaissance-costume?ga_order=most_relevant&ga_search_type=all&ga_view_type=gallery&ga_search_query=peasant+dress&ref=sr_gallery-1-7&bes=1&edd=1&organic_search_click=1 Hooded Cloak for $45-70 https://www.etsy.com/listing/1320701296/medieval-viking-hooded-cloak-renaissance?ga_order=most_relevant&ga_search_type=all&ga_view_type=gallery&ga_search_query=renaissance+fair&ref=sr_gallery-1-25&pro=1&frs=1&edd=1&organic_search_click=1
Accessories can be a good way to grab something cheap and make something you already have in your closet look more renaissance, or add on to another costume. Belt for $15-40 https://www.etsy.com/listing/1260106046/medieval-leather-belt-loop-key-ring?ga_order=most_relevant&ga_search_type=all&ga_view_type=gallery&ga_search_query=renaissance+fair+belt&ref=sr_gallery-1-6&pro=1&frs=1&edd=1&organic_search_click=1 Armor Belt $60+ https://www.etsy.com/listing/1326025290/medieval-wide-leather-armor-belt?ga_order=most_relevant&ga_search_type=all&ga_view_type=gallery&ga_search_query=renaissance+fair+belt&ref=sr_gallery-1-46&pro=1&frs=1&edd=1&organic_search_click=1 Skirt Hikes $10-20 https://www.etsy.com/listing/872203983/skirt-hikes-for-renaissance-medieval-and?click_key=28a09d899ee267fdc7e8545398b38c784f8a2253%3A872203983&click_sum=dae9c3d6&ref=top_rated_narrowing_module_search-1&sts=1 Ring Belt with Knot $40+ https://www.etsy.com/listing/706492549/1-14-wide-leather-ring-belt?click_key=eb1d2440bdc68542d1cd568e07708dce5d914357%3A706492549&click_sum=d4619c2e&ref=top_rated_narrowing_module_search-4&frs=1 Moon Circlet $30 https://www.etsy.com/listing/709366654/moon-circlet-fairy-crown-woodland?ga_order=most_relevant&ga_search_type=all&ga_view_type=gallery&ga_search_query=fantasy+accessories&ref=sr_gallery-1-3&frs=1&edd=1&pop=1&organic_search_click=1 Potion Bottle https://www.etsy.com/listing/1043316480/leather-and-glass-potion-bottle-pink?ga_order=most_relevant&ga_search_type=all&ga_view_type=gallery&ga_search_query=fantasy+accessories&ref=sr_gallery-1-6&frs=1&bes=1&edd=1&sts=1&organic_search_click=1