I often get calls from potential clients asking to give them an idea about costs on reno before submitting offer on apartment or house. I most of cases give some ideas over the email or phone, but visiting is very overwhelming and has poor ROI. I understand a high demand on use of professional opinion and more accurate estimate before buying home.

Is there a home buyers guide that can give a home buyer an idea of how much "things" would cost? This could be useful for everyone :)

Even if there was such a guide it would be outdated the minute it was printed besides the things sushipup wrote. Better that they ask and if necessary pay for an estimate but in no way should you suggest any company to do the estimate.

well, when people shop for homes, they see dozens of properties and not everyone wants to pay few hundred for walk through and no contractor will keep going to showings.

I used to many years ago wne i was new to business but, soon realized return rate was 1% and stopped doing it for people i did not know. Existing clients is different story... I love going with them and discovering new spaces to transform.

However the issue is for people who do not have a relationship with contractor nor knowledge of this kind.

When buying a home, most buyers opt for a building inspection, and use a specialist who is often a retired contrcator. He/she gets a proper fee for the inspection, up to $500 usually. It would be a conflict of interest for a working contractor to do this job. However, it's not uncommon for a buyer to also call in a contractor to give estimates at the same time.

Actually, there are numerous calculators and guides to help in preparing an estimate for building a house or a garage and therefore probably on remodeling projects too. Just Google and you will find them.