https://welovebudapest.com/en/event/lakasvasar-6/
Browsing through some sites found this pop up market ...has anyone any experience of it ?
I haven't been to this one but to other pop-up markets in Budapest and find they are fun, usually there's food and drink as well and you can plan to spend an hour or so.
Ive never heard or been to that market, but close by to that is the Gozsdu Udvar, which is a series of interconnected courtyards that run for about a block. On Saturday & Sunday they have various venders that set up in the passageway, I think that would be a better option for you. https://www.tripadvisor.com/Attraction_Review-g274887-d276879-Reviews-Gozsdu_Udvar-Budapest_Central_Hungary.html