Looking to renovate in New York, but unsure how much your project should cost?  Welcome to The Bottom Line. Each column features a real-life estimate prepared by Bolster--a New York City company that has designed a transparent and enjoyable process for area homeowners doing major renovations—along with tips for scaling the project to suit your budget.

The Space 

Adjacent two-bedroom and one-bedroom apartments, totaling 2,555 square feet, in an iconic Tribeca condo building.  

The Wishlist

Valeria and Rafael (names changed to protect the homeowners' privacy) are a married couple with children, who recently purchased the one-bedroom unit next to their two-bedroom. They want to combine the apartments, creating a larger space that blends the units seamlessly and affords the family more privacy and room to stretch out.

Valeria, a chef, also wants to update the existing kitchen, which she feels lacks personality and needs more storage space; she’d like to change the cabinetry, add shelving for pots and pans, and put in new appliances.

 Inside the homeowners' Tribeca condo, pre-renovation. Taken by Bolster Architect Agustin Ayuso. 

Inside the homeowners' Tribeca condo, pre-renovation. Taken by Bolster Architect Agustin Ayuso. 

Additionally, the couple is considering whether to purchase the corridor that runs alongside the two apartments in order to create an easier entrance to the combined space—a change that could have the added advantage of increasing the home’s value. Valeria and Rafael plan on remaining in the apartment for at least a decade, which could mean seeing a significant appreciation by the time they’re ready to move.

As first-time renovators, Valeria and Rafael reached out to Bolster for guidance in understanding the nitty-gritty of what goes into an apartment combination, as well as to get a sense of the financial investment and timeframe it would take to get this renovation right.

The Budget

At the most basic level, Valeria and Rafael could combine the apartments simply by tearing down a wall. However, their priority is to create a larger unit with a seamless flow that looks like it has always been one apartment. They’re willing to invest up to $200,000 for the combination, and an additional $75,000 to upgrade the kitchen.

The Estimate

Within 48 hours of receiving Rafael’s initial email, a Bolster Specialist, General Contractor, and Architect visited the two apartments to get a sense of the space, as well as the owners’ wishlist for the renovation. Shortly after, the Bolster team produced their free Cost Estimate, with a narrow minimum / maximum range of costs. The Cost Estimate was tailored specifically for Rafael and Valeria’s home, using the information they provided as well as sample data from other, similar combinations in Manhattan condos that have been carried out through Bolster’s platform.

The Cost Estimate, which you can review in detail here, pegs the cost to do the full combination at between $265,405 ($104 per square foot) and $394,726 ($154 per square foot). A no-frills renovation, which would involve simply tearing down a wall, as well as “decommissioning” the second kitchen, would cost around $15,000. (Homeowners doing an apartment combination may only keep two kitchens if they have a letter from a rabbi to the Department of Buildings confirming their kosher status.)

Sophisticated homeowners, Valeria and Rafael understand where they can find savings if they opt for the more intensive renovation. For instance, by purchasing flooring from a neighbor who has remnants from a previous project, they can cut some costs. And by exploring various layout options for the combination, they can better grasp exactly how much appreciation to expect for the property.

While estimates traditionally aren’t as detailed or reliable as bids, Bolster says that out of 100 Cost Estimates that have progressed to the bid stage over the past five years, 98 have fallen within the stated minimum-maximum range.

 The Breakdown

  • Design Fees: $40,964 - $62,660 A Bolster Architect will help realize Valeria and Rafael’s vision for their home, from drafting initial sketches to designing an optimal layout to helping them with details like selecting fixtures and fittings that offer the best value for their money. Expert tip: Homeowners seeking a seamless look in their apartment combinations should consider having the architect design the kitchen, rather than purchase one from a high-end showroom. Your architect will have a more precise sense of how to create a sense of continuity throughout the unit. Bolster can help with either option.


  • Compliance Fees: $8,100 - $13,225 Compliance fees cover things like expediting—that is, making sure all the required documents and permits are quickly filed and processed at the Department of Buildings—and depend on the final scope of the project. Valeria and Rafael are beginning design a year in advance of construction, allowing plenty of time to plan the project, and determine its scope and timeframe. Once those considerations are settled, this number will be firmed up.


  • Rough Construction & Labor Costs: $108,170 - $159,420 These costs cover the raw materials needed for the renovation—think sheetrock, plumbing pipes, electrical conduits, and carpentry—as well as the labor to install them. During the initial planning stages, these costs—which on typical renovations, are often hidden expenses—will be calculated using Bolster’s Renovation Cost Algorithm to give Valeria and Rafael clarity on what percentage of their budget will go toward these materials.  


  • Fixtures, Finishes & Appliances Allowance:  $21,634 - $31,884 For Valeria and Rafael, their top priority is to devote the lion’s share of their budget toward high-quality construction and design, rather than on super-luxe appliances, fixtures, and fittings. For these details, they’ll likely select mid-end options that are solid, robust, and durable, but not necessarily name brand.


  • Project Management & Mandatory Insurance: $32,451 - $47,826 Indirect costs, like labor and insurance, vary significantly depending on the scope of a project. Valeria and Rafael’s apartment is in a development built in 2008, which reduces the chance of complications or unforeseen issues during construction due to problems that can strike older properties, like asbestos or structural defects from aging floors and ceilings. And luckily for the couple, the flow of the two apartments’ layout makes for a smooth combination; the new, larger unit will be divided from left to right into two wings, giving both parents and children privacy. Expert tip: Remember that having a condo versus a coop gives you more flexibility in changing your layout.


  • Contractor Overhead & Profit: $54,085 - $79,710 These fees are standardized at Bolster and calculated as a percentage of the project budget, so they depend on Valeria and Rafael’s overall construction costs. The couple’s Bolster Contractor and Architect will be fully transparent about where each and every dollar is going, so that Valeria and Rafael can lock in their fixed-price cost and avoid mid-renovation change orders, which can send project expenses soaring.


  • Bolster Financial Guarantee: $10,817 - $15,942 Approximately half of renovation projects in this country go 40% to 200% over budget; moreover, each year, 17.2% of New York contractors go out of business, taking 77,245 projects and $700 million of clients’ money with them. If Valeria and Rafael use a non-Bolster contractor, their financial exposure to cost overruns and contractor failure on their project amounts to $233,418. By choosing a Bolster contractor, Valeria and Rafael’s exposure to cost overruns will be limited to $28,315. (These numbers are calculated through Bolster’s platform, which measures the financial exposure to owners on their project when hiring a traditional general contractor, who carries all the usual industry-standard overrun and business failure risks, versus a Bolster contractor, who comes with a set of quantifiable protections that address, mitigate and in some instances, eliminate, overrun and business failure risks.) Or, for a cost of $10,817 to $15,942, depending on the finalized project budget, they can protect their renovation and their finances by having their project financially guaranteed by Bolster, reducing their exposure to cost overruns to $0.

The Bottom Line

As first-time renovators, Valeria and Rafael had trouble imagining what an appropriate budget for their project should be. Armed with reliable information from Bolster’s Cost Estimate, they’re now committed to spending between $275,000 and $300,000 on their apartment combination. The certainty has given them the confidence to make on the outside corridor to put the finishing touches on their new home.

Their next step is to engage their Bolster Architect, who will deliver a low-cost set of sketches for potential layouts, enabling Valeria and Rafael to “see” what their new home could look like. The couple plans to move forward, taking the next year to save and then working through the Bolster platform to do their renovation the right way, resulting in an expanded and revamped home that their family can enjoy for years to come.

About Bolster’s Cost Estimates

Homeowners rarely get reliable and accurate information upfront about their project's total cost before hiring professionals. Bolster's Free Cost Estimate—typically provided within 2 days of a walk-through of the project--provides a statistically accurate range of costs from proven professionals to help you make informed decisions about the scope, design and cost of your renovation project, before you incur professional fees.

About Bolster

Every year, New Yorkers waste over $700M following the usual renovation process. Bolster is different, using a scientific approach to match you with the highest-quality professionals and financially guarantee your project is delivered beautifully for a fair price - all at no extra cost.

To start your major home renovation project, visit bolster.us 

Read more from Bolster:

The Bottom Line

The Winning Bid

Here's how much it costs to renovate a Tribeca rooftop

Why are high-end bathrooms so low-tech? 

Here's how long it takes to gut renovate a three-bedroom apartment in NYC

Should you hire an architect or a contractor first? 

How to find a great contractor in NYC

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