In the financial projections in a business plan, your assets are supposed to be worth what you paid for them, less depreciation; not what you could sell them for. That’s the value on your books, like it or not. Standard accounting practices, also known as GAAP (for Generally Accepted Accounting Principles), does it that way.
This comes up because it frustrates people who want to present their financial picture based on what their assets are worth, rather than what they cost. I get it. Financial convention, however, for centuries, has based the bookkeeping on the actual transactions.
It’s not that it doesn’t matter that your land and buildings, which are on the books for $150,000, are really worth $500,000. It does matter. It makes you happy. If you’re doing a business plan to be read by outsiders, you should include that fact in the text, because it does influence what your business is really worth. but it doesn’t belong on the books. On the books it should be $150,000 less depreciation.
Your consolation for that disappointment is that if you bought it for $150,000 and you put it on your books at $500,000, then you owe the government some taxes on the $350,000 of profit. Happily, the government agrees with financial principles, so it lets you keep those assets on the books until they are actually sold.
And then, finally, there’s that other problem. What if you had the assets at your estimate of their resale value, and then when you sell them, it turns out that the selling price was less than what you had estimated. Would a sale at $400,000 for assets that cost $150,000 be a $100,000 loss (from your $500,000 estimate) or a $250,000 profit? Of course it’s a profit, not a loss.