Are these fast-growing stocks a buy after today’s updates?

Shares of online fashion retailer Boohoo.Com (LSE: BOO) are up by 9% to 81p this morning. In a trading update, Boohoo said it now expects sales to rise by 28%-33% this year, compared to previous guidance of 25%-30%.

This upgrade is more significant than it might seem, because of the effects of operational leverage. What this means is that as sales rises, a company’s fixed costs — such as rents — represent a smaller part of each sale, increasing profit margins.

Boohoo said today that it expects operational leverage to result in increased profit margins this year. Although no specifics were provided, I now expect current forecasts for earnings of 1.44p per share to be upgraded.

With a forecast P/E of about 50, Boohoo looks expensive. But this group is delivering profitable, cash-generative growth at an impressive rate. Today’s share price could easily look fair in a year or two’s time.

I believe existing Boohoo shareholders should continue to hold. New investors might want to wait for a short-term pull-back, in order to maximise future gains.

Is this 8.8% yield real?

Sofa company SCS Group (LSE: SCS) rose by 5% this morning, after reporting a 14.8% increase in like-for-like sales for the year ending 30 July. David Knight, ScS chief executive, said that trading was strong through the referendum campaign, and has remained so since then. Fears that Brexit could lead to a slump in sales appear to be misplaced.

Full-year profits are expected to be in line with current expectations. That suggests the firm’s dividend guidance should also remain valid.

ScS paid an interim dividend of 4.67p per share earlier this year. The company said it expected the final dividend to be roughly twice this size, implying that the total dividend for the year could be 14p.

If this guidance is maintained, then ScS shares currently offer a prospective yield of 8.8%. The firm’s half-year numbers suggest this generous payout should be affordable. At the end of January, ScS had net cash of £32.2m, or about 80p per share.

On this basis, the shares’ forecast P/E of 8 looks very cheap, notwithstanding the risk of a Brexit slowdown.

Is Neil Woodford wrong?

Top fund manager Neil Woodford has a 27% stake in business energy supplier Utilitywise (LSE: UTW). The firm’s shares rose 3% this morning after it announced the appointment of a new chief executive. But founder and current boss Geoff Thompson isn’t going far — he’s becoming the group’s executive chairman.

It’s unusual to have an executive chairman and a chief executive. The chairman’s role is normally non-executive. Mr Thompson’s sideways move also goes against corporate governance recommendations.

However, I’m more concerned about the financials. Utilitywise fell by 10% on Monday after the group warned that performance had been disappointing. Full-year revenue is now expected to rise by about 18% to “at least £82m”, compared to consensus forecasts of £90m.

Profits are also likely to be disappointing, with adjusted EBITDA expected to rise by less than 2% to £18m. One bright spot was that the group’s net debt has been repaid, suggesting cash flow is improving.

However, rising sales and flat profits suggest to me that profit margins are falling. Although the shares’ P/E of 6.5 looks cheap, I’d like to know more before buying.

Today's small-cap growth tip

Boohoo, ScS and even Utilitywise could deliver strong growth from current levels. But our expert analysts have zoomed in on a different retail stock, which they believe deserves the title 1 Top Small-Cap Stock From The Motley Fool.

The company concerned is a UK-focused business with exposure to Europe. The shares look cheap to me and this firm's management has a track record of strong growth.

I'd urge you to take a look today, as our analysts believe this stock could re-rate sharply higher. To download your free, no-obligation report, just click here now.

Roland Head has no position in any shares mentioned. The Motley Fool UK has recommended We Fools don't all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors.