Pre planning and having a set limit is the way to do it but the hardest part will be sticking to it. Like for me at the furniture store, I had a budget but the bar stools we had planned on buying exceeded our budget. We knew the home wouldn't look right with that empty space so we bent out budget slightly for the bar stools...they were about $80 total. I miscalculated the TVs and home theater system cost by 50% so I ended up getting a BB CC to help with that. I'm actually happy about it as the additional credit line is helping my credit and it is 0% APR for 24 months. We still have ample reserves but we ended up expanding our budget a couple of times. I feel satisfied with the initial state of the house and I am enjoying it. But having a budget in advance definitely helped us spend less even though we ended up exceeding it.
Cards: Orchard Bank ($1100) | Cap1 Cash Rewards ($2500) | Chase Freedom ($1000) | Best Buy ($2500) | Discover It ($1000) | Barclay Rewards ($2500) | Current scores: EX FAKO: 684, CK TU: 649, FICO EQ: 680, FICO TU: 698, FICO EX: 658 Happy Homeowner Since 2/6/13! 
Last App: 4/5/13 Gardening until July 2014
Good idea, I've already made a list of the new things I want. But after all this stress over 13 little points, I'm going to do one room a month and work overtime for those extras.
Starting Score: 492-TU04, 480-EX FICO V2, 467-EQ Beacon 5 (Via Mortgage PreQual March '12)