What Level Best is
Level Best is a web application for planning, budgeting and running house and garden projects in the United Kingdom. It is made in Kent by Richard Cowtan, and it exists because his own renovation went sideways in the ordinary way: not one disaster, but a budget nobody could see clearly and a sequence nobody had written down.
What it does
You describe the project in your own words. Level Best asks the scoping questions a professional would ask, then drafts a costed budget with a best case and a worst case for every line, a task list, and a schedule that knows how long the slow parts take: a planning decision is eight weeks by statute, and the bifold doors you order late will hold up everything behind them.
From there it is a working tool rather than a report. It reads builders' quotes and compares them line by line against your budget. It finds rated local trades near the project's postcode. It checks what the public planning registers say about the site, including listed building status and what the neighbours were granted permission for. It tracks committed spend against forecast, shows the cashflow month by month, and keeps a decision log so that in October you can remember why you chose the more expensive roof in June.
What it does not do
It does not survey your house, and it says so. Its estimates are ranges built from published UK cost benchmarks and its own reading of your project, not quotations; a real quote from a real builder beats its numbers, which is why it is built to collect and compare those quotes. It is not an architect, a structural engineer or a planning consultant, and where those are what a project needs it says that plainly. Nothing in it is legal or planning advice.
What it costs
One project is free, with no card required. Paid membership is £7 a month and removes the single-project limit; a Professional plan at £29 a month adds client sharing and support for people running projects for others. Prices are on the home page.
The rules it will not trade away
Level Best can offer to post a job to an outside trade network, and may earn a commission when such a request is taken up. Three rules govern that, stated here because they are the kind of thing usually left unstated: the offer is always labelled as an ad next to the button rather than in a footer; the organic trade search results are never reordered by commission; and the whole layer can be switched off by the customer, permanently, from their account page.
Common questions
Who is Level Best for?
Homeowners planning real building work: an extension, a loft conversion, a kitchen, a whole-house renovation, a big garden project. It earns its keep when there are several trades to sequence and tens of thousands of pounds at risk, rather than on a single small job.
Is the AI making up the prices?
The ranges start from published UK cost benchmarks, dated and sourced, and are adjusted for what you say about the project. The method, including its weaknesses, is written up on the blog. As for accuracy: enough to plan with, and it says so when the point comes to stop reading its number and go and buy a proper one.
Where does my data live?
In the UK company's Supabase database in the EU, readable only by you and the people you explicitly share a project with. The full detail, including every third party involved and why, is in the privacy policy.