For Sale Used Go Cart Frame Only What Point Of Sale Package (software+hardware) Would You Recommend For My Hotdog Food Cart?

What point of sale package (software+hardware) would you recommend for my hotdog food cart? - for sale used go cart frame only

I did buy a small food businesses to hot dogs in one of the malls here in our region. Cash register with IM is 15 years and wants to move to a point of sale, but we have very little in the budget. I wonder if they can recommend POS cheap but reliable? Thank you!