First of all, Richmond, MA is a rural area that is part of The Berkshires. What applies in "the Citiies" has little bearing hear. Remember that renting here is a bit more complicated. We have no MLS for rentals, so a great deal of the work will fall squarely on your shoulders.
Right now (August of 2012), we are experiencing a rapidly declining inventory of properties on the market, along with double digit percentage increases in the number of properties going under contract and closing over the same period last year. There are more multiple offer situations, but only careful negotiation bring them to fruition. Listings of well-priced homes are selling in 45-60 days, at an average of 92-94% of listing price. We are also in our summer buying season for second homes, so it might be worth considering taking advantage of the uptick in demand to price your property correctly and sell it rather than rent it.
When you rent a property out, there are many things of which you need to be aware. If your home was built prior to 1978, you are subject to MA Lead Paint laws. If a child under 6 moves into the property for a period longer than 30 days, and lead was used in any stains or paints on the property, you are obligated by law to remediate at your expense. YOU MAY NOT REFUSE TO RENT TO SOMEONE WHO HAS A CHILD, unless your property has only one bedroom and the child is over 6 months old. If a child under 6 years old moves in, you are required to test for the presence of lead, and once the results of that testing is known you will be obligated to disclose that information from that point on.
You will need to be acutely aware of Fair Housing laws. Know the requirements and follow them to the letter...there are testers out there and the penalties are steep. For instance, can you advertise that you will not take on smokers or pet owners? Can you describe your property as great for a family or a singe person? Can you describe the location as near a church or synagogue?
How comfortable are you collecting rents if things get contentious? How will you handle being called in the middle of the night for a clogged toilet? Will you be able to take care of emergencies from afar? Do you know how to legally handle deposit/escrow checks? Will you still be able to afford a larger home if the rent doesn't come in or if the property is vacant, still costing you for heat, taxes, repairs, utilities, insurance?
House prices are beginning to rise, and interest rates may follow suit. Selling now will allow you to purchase your larger home elsewhere at it's most affordable. If you delay, prices rise and interest rates go up, you may not be able to afford as much house later. The financing question also comes into play. Will a lender give you a loan for a new primary residence while you use the former property as a rental?
Talk with a local lender. They will be happy to give you sound advice. Have a local Berkshire Realtor do a market analysis for you so you know what you are likely to get for your property. Have that agent refer you to a Realtor in your new community and have them show you SOLD property information so that you can see what your budget is likely to afford there.
Then, be really, really honest with yourself. Knowing what you can reasonably afford, what you can reasonably expect to get for your present property, and how well you can deal with legalities and inconvenience, decide whether renting or selling is a better option for you.