 For investors willing to shoulder additional risk, these may be the best of times for buying stocks. Writing at Morgan Stanley, Michael Wilson, the firms head of US equity strategy, firmly believes that the signs are bullish, and that current conditions in the markets closely resemble those of March 2009. That was when market turned upwards after the 2008 financial crisis, beginning the longest bull run in history.Wilson wrote, A significant driver of our bullish call ... was based on the equity-risk premium reaching the same levels observed in March 2009. If theres one thing weve learned over the past 10 years, its that when risk premium appears you need to grab it before it disappears.Investors can maximize that premium by finding stocks with the lowest share price and the highest upside potential in short, by buying into high-rated penny stocks. These equities, typically trading for under 5 per share, offer a minimal cost of entry and can sometimes show triple digit upside potential. Weve used the TipRanks database to pull up the details on three such opportunities. All three have received enough support from Wall Street analysts to earn a Strong Buy consensus rating. Not to mention each boasts substantial upside potential of over 100.Organogenesis Holdings ORGOOrganogenesis subsidiaries operate in the world of medical tech, developing new technologies in two markets: wound care, and surgical and sports medicine.Despite a sharp increase in earnings losses during the first quarter, Organogenesis had good news to report. Top-line revenue came in at 61.7 million, modestly beating the forecast but growing 8 year-over-year. Revenues grew substantially in both the wound care and surgical and sports medicine segments. The company finished the quarter with 46.9 million in cash on hand.Organogenesis returned to public trading at the beginning of last year, after 16 years as a private company. Like many high-tech medical companies, it has not yet turned a profit but it does have exciting prospects for successful products in potentially lucrative sales fields.This potential lies behind 5-star analyst Richard Newitters comments. In his report for Leerink, Newitter writes, As a relatively new public company, we believe ORGO has yet to be fully discovered by investors with a below-peer valuation that in our view is highly dislocated from the companys longer-term sales growth prospects, healthy end-markets, and a scalable long term 70 GM business. Ultimately, as investors increasingly come to appreciate ORGOs potential for sustainable DD top-line growth increased profitability prospects into the out-years, we think the multiple will expand driving shares higher.In line with his upbeat outlook, Newitter rates ORGO shares a Buy, and his 7 price target implies a 112 upside potential. In short, the analyst believes that now is the time for investors to get in at the ground level. To watch Newitters track record, click hereAll in all, Wall Street analysts are unanimous in their endorsement of the shares. Organogenesis stock has been endorsed with buy ratings by all four of the analysts who have voiced an opinion over the past year. Meanwhile, the consensus estimate of analysts is that ORGO, currently trading at 3.33, should rise over 120 to hit 7.50 within a year. See Organogenesis stock analysis on TipRanksUsio, Inc. USIONext up on our list is a tech company, Usio. This company provides payment solutions for merchants and billers, offering credit, debit, and prepaid card processing, and automated clearing house payment platforms. Usio aims to combine card issuing and merchant payment processing options into a one stop shop platform.A small-cap company, with a market capitalization of just 32 million, Usio is nevertheless in a strong position despite the coronavirus market disruptions. While markets have lost heavily in the current bear cycle even accounting for the rally were experiencing USIO shares have outperformed and are trading above their late-February levels. The company reported an 18 growth in revenues for Q1 2020, to 7.8 million, along with steady progress towards break-even cash flow. Usio ended the quarter with 1.7 million in cash on hand. These positive results came despite a net loss in Q1 but it is important to note that Usios Q1 losses were 50 lower than in Q4, and beat the quarterly expectation by 14.Usio has also been able to take advantage of Congressional stimulus funds. The company qualified for a CARES Act loan of 814,000. The loan comes with generous repayment terms, and provides Usio with needed liquidity to meet the coronavirus crisis.Ladenburg Thalmann analyst Jon Hickman sees a clear path forward for Usio, writing, ...we believe Usios current market valuation is not reflective of the value of the companys growing presence in the digital payments space. Given the expected increasing revenue growth and future earnings potential, we believe the company should be valued more in line with its current and potential earnings growth.Hickmans Buy rating is bolstered by his 4.50 price target, which indicates confidence in a robust 142 one-year upside potential. To watch Hickmans track record, click hereUSIO shares have a Strong Buy analyst consensus rating, and it is unanimous. All three of the analysts who have reviewed this stock recently have come down with Buy recommendations. The shares are selling for just 1.75, and the average price target matches Hickmans 4.50. The upside potential, 142, implies that this stock will more than double in the coming year. See Usio analyst ratings on TipRanksRamaco Resources METCThe last stock on our list is Ramaco, a coal mining company operating in Pennsylvania, Virginia, and West Virginia. The company focuses its output on metallurgical coal, a grade used to produce the refined coke that is required in the steel industry.Even with economic activity greatly reduced in Q1 by the responses to the coronavirus crisis, Ramaco reported a quarterly profit. The 5-cent EPS came in 67 over the forecast. Earnings werent the only positive in the Q1 report. Revenue came in at 41.9 million, or 2.5 over the estimates.Ramacos main sales theater is the eastern US but demand there has collapsed due to the economic shutdowns. The company has countered this by turning to foreign customers and accepting aid through the Congressionally passed Paycheck Protection Program. The 8.4 million PPP loan has shored up the companys liquidity position, and allowed it to resume operations at two mines which were idled on April 1.Lucas Pipes, covering the industry and Ramaco stock for B Riley FBR, notes, ...management pointed to a number of marketing successes in the first quarter, including renewing a relationship with a major European customer, their first test shipment to Asia, and a notice that their product was approved for purchase by major integrated steel mills in Brazil ... While we currently see investors focus on liquidity, then capital returns, and growth opportunities last, we regard these growth projects as long-term options when market conditions improve.These successes put Ramaco in a solid position to move forward, and Pipes rates the stock a Buy. His price target, at 8, implies a sky-high 221 upside potential this year. To watch Pipes track record, click hereIts not often that the analysts all agree on a stock, so when it does happen, take note. Ramacos Strong Buy consensus rating is based on a unanimous 4 Buys. The stocks 5.25 average price target suggests a potential upside of 103 and a change from the current share price of 2.56. See Ramaco stock analysis on TipRanksTo find good ideas for stocks trading at attractive valuations, visit TipRanks Best Stocks to Buy, a newly launched tool that unites all of TipRanks equity insights. 