Personally, I think location, location, location. I saw some great houses in crappy areas.
Try Perfect Place 77 - Perfect Masterpiece if you want to spend 50m.
https://www.pf.co.th/th/project/single-house/perfect-place/sukhumvit77-suvarnabhumi?utm_source=googlemap&utm_medium=organic&utm_campaign=googlemap_house
https://www.pf.co.th/th/project/single-house/perfect-masterpiece/sukhumvit77
Estate is nice. Lived there for years.
Right next to Paseo, Robinsons, Homepro, Makro. 10 minutes from the Airport.