A mentor is worth paying for if they stop you pursuing one bad site. The planning phase on even a small scheme means surveys, consultant reports and application fees, all spent months before a decision arrives and none of it refundable — to find out something an experienced developer could have told you in ten minutes.
That is the entire case, and it is a good one. This post covers what a mentor actually adds to site sourcing, what to ask before you pay anyone, and how to tell mentoring from a course with a mentor on the cover.
Why site sourcing is where beginners lose money
Sourcing is not browsing listings. It is forming a view on whether a specific piece of land could get planning permission — which means reading the local plan, the designations over the site, the authority’s recent decisions and the reasons behind its refusals.
Get that wrong and everything downstream is wasted. The appraisal is precise about a scheme that will never be consented. The finance is arranged for a purchase that should not happen. And the cost only shows up months later, when the decision notice arrives.
Meanwhile the numbers say there is room for people who get it right. England added 208,600 net additional dwellings in 2024-25, 6% down on the previous year (MHCLG, published 20 November 2025), while small and medium builders have gone from 39% of supply in 1988 to around 10%. Demand for consented land is not the problem. Getting land consented is.
What a mentor actually adds
- They kill bad sites fast. The most valuable thing an experienced developer does is say no in ten minutes, for a reason you had not considered — access you cannot achieve, a levels problem, a designation, a neighbouring objector with a track record, a policy that reads one way and is applied another.
- They know the authority. Planning is national policy applied locally, and local application varies enormously. Someone who has taken schemes through your council knows which officers are pragmatic, what the committee refuses against advice, and what the last three appeal decisions turned on.
- They price things properly. Beginners underestimate professional fees, Section 106 and CIL, biodiversity net gain, abnormals and finance costs. A mentor reviewing your appraisal is the cheapest correction you will get.
- They introduce you. A planning consultant who takes your call because of who sent you is worth more than a list of names.
- They make you finish things. Analysis paralysis is the standard failure mode for people doing this around a job. Somebody expecting an answer next week is a surprisingly effective cure.
What to ask before you pay anyone
Mentoring in property has a thin line between genuine help and a repackaged course. Ask these, and be suspicious of vague answers:
- What have you developed, where, and when? Addresses and application references, not adjectives. You can look up every one of them on the council’s planning portal.
- Are you still doing deals? Someone whose income is now entirely teaching is teaching a market they left.
- How much of this is one-to-one? Recorded modules and a group call are a course. That can still be worth the money — but price it as a course.
- What do you get paid, and when? A fee, a share of your profit, or both. All are legitimate; not knowing is not.
- Who carries the cost if planning fails? This is the one that separates a mentor from a partner.
Mentoring versus partnership
A mentor advises and you carry the cost. A partner puts money in beside you. They are different products and the second one has its incentives in the right place — nobody funds a planning application on a site they think will fail.
BOOM! Planning Partners works that way: they fund 100% of the planning costs on a site you source and split the uplift 50:50 when it sells, with deal review and structured training alongside. If the application fails, the loss is theirs. That is worth understanding as a category, whoever you end up working with — if the person advising you has nothing at stake, the advice is free to be wrong.
What to do before you look for a mentor
Turn up with a site. A mentor given a shortlist and your reasoning is a different conversation from a mentor given a blank page, and you will learn ten times as much from the first.
So do the work first: pick one authority, learn how it treats settlement boundaries, build a shortlist using the routes in our guide to off-market sourcing, and have a view on how you would structure the deal. Then find someone to tell you what is wrong with it.
