Royston Wild has no position in any of the shares mentioned. The Motley Fool UK has no position in any of the shares mentioned. Views expressed on the companies mentioned in this article are those of the writer and therefore may differ from the official recommendations we make in our subscription services such as Share Advisor, Hidden Winners and Pro. Here at The Motley Fool we believe that considering a diverse range of insights makes us better investors. Our 6 ‘Best Buys Now’ Shares I would like to receive emails from you about product information and offers from The Fool and its business partners. Each of these emails will provide a link to unsubscribe from future emails. More information about how The Fool collects, stores, and handles personal data is available in its Privacy Statement. It’s no mystery why the Shaftesbury (LSE: SHB) share price has exploded 42% since 5 November. A series of successful vaccine breakouts since the autumn, and the impressive rollout of these virus combatants since then, have raised hopes that shoppers and workers will flood back into its retail, leisure and office spaces en masse.The London-focused property play is expected to endure a 45% earnings fall in this fiscal year to September. But City analysts anticipate a near-90% bottom-line bounceback in financial 2022. Can the Shaftesbury share price keep on chugging higher then?5G is here – and shares of this ‘sleeping giant’ could be a great way for you to potentially profit!According to one leading industry firm, the 5G boom could create a global industry worth US$12.3 TRILLION out of thin air…And if you click here we’ll show you something that could be key to unlocking 5G’s full potential…Four key issues for the Shaftesbury share priceThere are several things I’d consider when looking at the Shaftesbury share price:#1: A worsening Covid-19 crisis. The government’s plan is to gradually reopen the economy with all lockdown restrictions set to end by 21 June. However, the emergence of a third wave on these shores is something prime minister Boris Johnson is publicly predicting. And it could scupper that re-opening roadmap for British businesses.#2: The end of furlough schemes. The Local Data Company says more than 11,000 stores in the UK closed in 2020. It predicts that another 18,000 could disappear this year following the collapse of high-profile retailers such as Debenhams and Topshop and the slimming down of retailers such as John Lewis. But the worrying news doesn’t end here as the body warns that the end of the government’s furlough support schemes later in 2021 could create even more casualties over the next two years.#3: The rise of homeworking. It’s been suggested the national lockdowns of the past year have prompted a sea change in the way modern workers go about their business. And it’s led to speculation that demand for office space, like those operated by Shaftesbury, might fall as flexible working practices become the norm.#4: High valuation. The recent Shaftesbury share price explosion makes the company look mighty expensive. At current prices, the UK property share trades on a forward price-to-earnings (P/E) ratio of 130 times. This sort of sky-high valuation leaves Shaftesbury in danger of a sharp share price correction if trading performance worsens and predictions of a strong earnings bounceback start to look wobbly.In conclusionI won’t suggest Shaftesbury is a basket case. All of its properties are located in key entertainment, tourist and shopping districts including Soho, Covent Garden and Chinatown. The streets around these timeless areas will be packed out again when the Covid-19 crisis finally ends. Furthermore, lots of the company’s tenants are niche retailers whose long-term outlooks are much stronger than much of the broader retail sector.Still, in my opinion, Shaftesbury’s rocketing share price factors in all of the good news regarding the end of lockdowns. And, as I say, this leaves this UK share in danger of slumping again if news flow on this front worsens. With the business facing significant long-term headwinds like e-retail and the rise of homeworking, I’d rather buy other stocks for my ISA right now. Renowned stock-picker Mark Rogers and his analyst team at The Motley Fool UK have named 6 shares that they believe UK investors should consider buying NOW.So if you’re looking for more stock ideas to try and best position your portfolio today, then it might be a good day for you. Because we’re offering a full 33% off your first year of membership to our flagship share-tipping service, backed by our ‘no quibbles’ 30-day subscription fee refund guarantee. Royston Wild | Thursday, 25th March, 2021 | More on: SHB Click here to claim your copy now — and we’ll tell you the name of this Top US Share… free of charge! “This Stock Could Be Like Buying Amazon in 1997” Image source: Getty Images. Simply click below to discover how you can take advantage of this. See all posts by Royston Wild Enter Your Email Address I’m sure you’ll agree that’s quite the statement from Motley Fool Co-Founder Tom Gardner.But since our US analyst team first recommended shares in this unique tech stock back in 2016, the value has soared.What’s more, we firmly believe there’s still plenty of upside in its future. In fact, even throughout the current coronavirus crisis, its performance has been beating Wall St expectations.And right now, we’re giving you a chance to discover exactly what has got our analysts all fired up about this niche industry phenomenon, in our FREE special report, A Top US Share From The Motley Fool. The Shaftesbury share price has rocketed 40%! 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