It is highly likely that your mortgage payments will go up if you decide to let it out, so of course that will need to be taken into account. Yield is about 5% which is on the cusp of an investment that makes sense. We're keeping our options open about future rental potential - current yield is around 6.5% but ultimately I think we'd be better off using the equity to get into a better location.
Regardless of whether or not you head down the sale or rental place, if you want to get a great result without spending a fortune, try and find decent second hand stuff rather than going for new. I got a £500 oven for £20 that was "broken" and tripping the MCB. A replacement fan unit for £10 and it's as good as new. We have basically bought all of our appliances used (but all <4 years old) and have done it all for less than a new dryer would cost. I also picked up a pair of solid wood lockers and chest of drawers for £40 that are currently in the shops for £250. This has meant that we've been able to channel money to stuff that's more important and should be a lot easier in the UK!
Regardless of whether or not you head down the sale or rental place, if you want to get a great result without spending a fortune, try and find decent second hand stuff rather than going for new. I got a £500 oven for £20 that was "broken" and tripping the MCB. A replacement fan unit for £10 and it's as good as new. We have basically bought all of our appliances used (but all <4 years old) and have done it all for less than a new dryer would cost. I also picked up a pair of solid wood lockers and chest of drawers for £40 that are currently in the shops for £250. This has meant that we've been able to channel money to stuff that's more important and should be a lot easier in the UK!