What do you trust for a first-pass rehab estimate?
New to Real Estate · Houston · Member since 2026 · 80 posts · 64 votes
For first-pass rehab numbers, what are you actually trusting before a contractor walks it?
I’m talking early stage: photos, inspection report, rough notes, and you’re trying to see if the deal is even worth chasing.
Are you using a spreadsheet, price per sqft, contractor gut check, past projects, or just adding a big contingency?
Also, what line item usually ends up being the most wrong?
@Ali Kalaei, a few thoughts:
1. I don't like things like price per sq ft because unless its a simple cosmetic rehab that will not account for the vast differences in the scope of work. For example, one rehab might need a new HVAC, roof, etc while another is mostly cosmetic.
2. Even among rehabs that are cosmetic, not everyone will do it the same. Some work more with what is there while others do more demo and replace with new.
3. Here is a question for you, does the rehab estimate need to be accurate?? The answer is NO!
4. You use an estimate up front to underwrite, but a single accurate estimate doesn't help you are much as you think. You also want to identify the risks/uncertainties because its an ESTIMATE afterall. You want to know that the expected outcome is good, BUT ALSO that if the uncertainties lead to more cost or scope/time changes that the deal is still solid.
5. Even when you are working with the estimate to manage the project to completion. Its more useful to have a well considered scope of work that didn't start off with severe limitations of time and scope. The money is estimated afterall, and without flexibility in time or scope you cannot manage the money as things evolve during a project.
6. The scope of work and time are actually part of your estimate!
Time can be COSTLY! Carrying costs, hard money costs etc can be very expensive on some projects.
Scope of work is also important! If you are planning a bare minimum scope you have less flexibility to adjust the scope to manage time and money!
7. In case you haven't caught on, there is a project management principle that basically says that a "project" has 3 main components: Scope, Time, and Money. You can often adjust 1 or 2 of them to manage the 3rd.
8. You can adopt a methodology to answer the question you need answered with your estimating without focusing solely on getting a precise money estimate!
@Ali Kalaei, a few thoughts:
1. I don't like things like price per sq ft because unless its a simple cosmetic rehab that will not account for the vast differences in the scope of work. For example, one rehab might need a new HVAC, roof, etc while another is mostly cosmetic.
2. Even among rehabs that are cosmetic, not everyone will do it the same. Some work more with what is there while others do more demo and replace with new.
3. Here is a question for you, does the rehab estimate need to be accurate?? The answer is NO!
4. You use an estimate up front to underwrite, but a single accurate estimate doesn't help you are much as you think. You also want to identify the risks/uncertainties because its an ESTIMATE afterall. You want to know that the expected outcome is good, BUT ALSO that if the uncertainties lead to more cost or scope/time changes that the deal is still solid.
5. Even when you are working with the estimate to manage the project to completion. Its more useful to have a well considered scope of work that didn't start off with severe limitations of time and scope. The money is estimated afterall, and without flexibility in time or scope you cannot manage the money as things evolve during a project.
6. The scope of work and time are actually part of your estimate!
Time can be COSTLY! Carrying costs, hard money costs etc can be very expensive on some projects.
Scope of work is also important! If you are planning a bare minimum scope you have less flexibility to adjust the scope to manage time and money!
7. In case you haven't caught on, there is a project management principle that basically says that a "project" has 3 main components: Scope, Time, and Money. You can often adjust 1 or 2 of them to manage the 3rd.
8. You can adopt a methodology to answer the question you need answered with your estimating without focusing solely on getting a precise money estimate!
For first-pass rehab numbers, what are you actually trusting before a contractor walks it?
I’m talking early stage: photos, inspection report, rough notes, and you’re trying to see if the deal is even worth chasing.
Are you using a spreadsheet, price per sqft, contractor gut check, past projects, or just adding a big contingency?
Also, what line item usually ends up being the most wrong?
I think it depends on how experience you are and the complexity of the rehab. I would never trust my first pass personally. If I pressed for time, I would use a price per sqft, however that would be just to get an offer in. I would reverify everything.
Ideally you can do a full scope of work. I'll make an offer based on that, HOWEVER, during my inspection period I always have a general contractor give a detailed estimate if I have not already gotten one.
It's easy to overlook items that seem fine at initial glance. A porch for example. It appears fine at first glance and seems structurally fine. Then it turns out its missing footings, rim joist, etc and has to be completely rebuilt because it's not to code. I know that one from personal experience.
Ali I trust a checklist and local calibration more than any single rule of thumb or software. The first pass is not supposed to be perfect. It is supposed to keep you from fooling yourself before you spend more time and money on a deal that does not pencil out.
Here is the logic I use to keep my numbers grounded. First break the property into systems and not just rooms. I look at the roof and structure and exterior and windows and electrical and plumbing and HVAC and kitchen and baths and flooring and paint and trim and landscaping and permits and holding costs. I mark every single line as light or medium or heavy or unknown. Unknowns never get optimistic numbers. They get a fat contingency or they get a reason to investigate further. The biggest mistake I see is pricing the visible finishes while ignoring the expensive boring stuff. A kitchen or flooring number is easy to guess from photos but the sewer line and electrical panel and roof decking and drainage and foundation and HVAC are the items that wreck your profit. If you cannot see it you have to assume it is a problem until proven otherwise. Second you have to calibrate against recent local bids. National averages or software estimates are too blunt for a first pass. Labor and permit expectations and disposal fees and material availability vary too much by market. I always compare my first pass against my actual completed projects in that specific neighborhood.
If the deal only works when every line item lands at the low end of your estimate you should pass or renegotiate. A good first pass tells you whether the deal deserves deeper diligence and nothing more.