Once you've made the decision to move, the next decision is, should you buy first or sell first? And, unless you are comfortable about the possibility of carrying two mortgages, this is a question that you should examine closely.
My 'general' rule of thumb is do first what ever is more challenging in your particular situation, but, always, try and do both buying and selling, in the same market.
What does this mean and how will you make the decision? Here are some factors that I have my sellers and buyers look at in order help them make an informed decision.
a) Look at the market charts for your area and housing type. What does the market data suggest? In the sale of your home, are you in a 'seller's market, a buyer's market, or is it a balanced market? In a balanced market, my suggestion is to sell first (providing you have found homes you 'would' purchase). This will give you the comfort of knowing exactly what your budget is with few surprises.
b) Examine what the 'market' is doing for your housing type, a condo will certainly be different than a single family home.
c) The 'market' charts should be up to the minute and give you some history so that you can easily identify trends. Is there an increase in the number of available homes, ( suggests a slowing market; trending toward a buyer market) or, is there an increase in the number of homes sold compared to those that are available.
d) It's the ratio, between what is sold and what's available that determines if we are in a 'sellers' market, a buyers market or a balanced market. If the market you are buying in is the same as the one you are selling in, then buy first in a 'sellers' market. Find the home you love, but, be prepared to have your home 'ready' and 'fit to sell', the moment you buy your next home.
e) An understanding of where the market has been and where it is will help you make an 'informed' decision about this very important question - buy first? or sell first? Because 'knowledge', will help you the minimize the risk!