Driving for dollar struggling to get ARV

[Genesis Pacheco]

Hello bigger pocket family so i have a two sellers that are telling me to give them an offer. Now i get that when you go on zillow and similar sites that you get the comps through there but i cant see the houses sold in that same block and also i dont have money for contractor just to give an  estimate so how can i determine an average cost for repairs without a contractor and get a close arv so i can make a good offer?