Rebuilts can be great for long term ownership. I have owned at least three. The first step is seeing that before picture and then closely checking any areas that have been repaired.

The problem is not necessarily the owning of the car it is the getting rid of it if you ever choose to do so. You should be aware some states will not allow them on the road, some insurance companies will not insure them, some finance companies will not finance them, many will additionally be burdened with a True Mileage Unknown title, most buyers are scared off and none want long explanations attached to the car they are considering.

As to value, determine the retail price for the perceived condition and multiply it by 50%. That should be close. If the title is branded with a True Mileage Unknown notation or if there are no detailed photos of the car prior to the repairs, I would offer the real world value of the nonmechanical parts only (minus the labor to remove them) or weight for scrape whichever is higher.