Ok. My bad. Was just looking at names alone. Didn't know they are bringing revenue. Value would than be a multiple (6mo-1 year) of current forward revenue I would think to end user. Have you thought of Flippa for potential auction/sale?
laptopbattery. net - (earned $5700 from Adsense in last 2 years, still earning $30 per month) purchased from godaddy for $211
1000dollarautos. com - (earned $1750 from Adsense from aug'16) purchased from godaddy closeout for $18
the value of the domains as is, cannot be compared to domains attached to a website that uses some type of monetization methods.
if you got them from gobaddly for $18 and $211 respectively, then that's what they were worth, at that time.
since nobody else though enough of them to bid higher.
now that you've put in some work, what they produce monthly, increases their value for sure.
though what multiple, or flat out price you ask for them, would be totally up to you.