Let me try to be succinct.... if you can find a really well-maintained Lagoon 37 or 42 then none of what I'm about to say matters.... but the ones in the price range you have been looking at generally need a lot of work and have not been well-maintained. Yachts are like cars in that: at a certain age, everything starts to fall apart. And the repair bills can be endless and you can spend all your time dealing with that and no time sailing/cruising. If you are a "tinkerer"/engineer-type then maybe this is quite alright ...(Are you?).......Different models reach the end of their "maintenance-free life" at different times (Leopard has the longest useful life) but generally the manufacturers have recently been using better materials and components so that the newer boats last longer. If I were in the market now and had to stick to a certain budget, I'd look for the newest boat possible by the best builder possible. The best production builders for 1999 onwards are Lagoon, Privilege, Leopard and Fountaine Pajot can be OK but stick to as late-model as possible and never buy one of their hull #1-5's (when new model comes out they always have screw-ups/leaks/issues and these dont always get remedied 100% by the manufacturer...FP has a terrible warranty reputation)....
The 37 and the 42 had some flaws which are not limited to the following and maybe these aren't deal-killers for you:
- their salons are small compared to more recent models....i.e., the newer-designed Mahe 36 has a larger salon than a Lagoon 42! But the 42 has a longer waterline and will sail a little better
- the headliners were constantly falling down and the replacement headliners can almost never look decent
- the flooring lasted about 15 years and needs replacing
- the way the windows are designed creates a "hothouse effect" in the tropics that broils you when sitting in the salon...there are some partial remedies for this (Note: that is why Lagoon went to vertical windows)
- on some 42's the engines were placed under the bunks and the inevitable oil spills/fuel spills on the engine stink up the interior. Some people get sick inhaling this....by the way, when I ran Moorings Yacht Brokerage for 10 years we went to Lagoon about this and they moved the engines aft and sealed them off from the living space but there are only a few models like this
- the 37 can hobby horse (pitch) quite a bit in certain seas
It may sound like I dont like these boats but I really do and have really fond memories of my 42 and 37....but I'm just saying a newer/smaller boat can usually give you the same amount of usable space and will "wear longer"